Giant Face of Ucanha: Huge Sculpted Mayan Mask Found in Mexico

A giant Mayan mask as tall as a person has been revealed at an archaeological site in the Mexican state of Yucatán. 

The mask, which depicts the face of an unknown deity or elite person, was sculpted from the building material stucco and dates back to a period in Maya history known as the Late Preclassic (about 300 B.C. — A.D. 250), according to the news outlet Novedades Yucatán.

The discovery was made in 2017 at the archaeological site of Ucanha, near the modern-day city of Motul, and since then researchers with Mexico’s National Institute of Anthropology and History (INAH) have worked painstakingly to restore it.

Stucco masks like this one “represent the faces of individuals with particular features that can be associated with deities or with characters of prominent social status,” INAH said in a statement.  

The mask is a stucco relief, a type of brightly-colored painted sculpture carved from a background of stucco. The Maya typically placed these masks around stairways with pyramidal bases, according to the statement.

Archaeologists have found similar reliefs in Acanceh and Izamal, but this is the first in Ucanha. The discovery is part of ongoing research into Mayan mounds found at the site. 

The mask was temporarily reburied after its discovery so that the structure was protected until it could be properly studied and preserved.

Samples taken from the structure revealed deterioration and it was re-excavated in 2018 so that archaeologists could restore it. 

During the restoration and conservation process, archaeologists reinforced fragile parts of the mask.

They also moved sections that had been displaced overtime back to their original positions. They also cleaned the surfaces to highlight the mask’s patterns and colors. 

The archaeologists completed the work in 2019, before reburying the mask for a final time. INAH said the goal of these efforts is to ensure the long-term preservation of the mask at the site, which does not have legal protection.

Hundreds of Artifacts Returned to Mexico by Arizona Homeland Security

Homeland Security Investigations (HSI) returned 277 pre-Columbian artefacts to Mexican officials Tuesday during a repatriation ceremony in the Mexican Consulate in Nogales.

The pieces were recovered after two separate investigations by HSI special agents assigned to Phoenix and Nogales, Arizona. Scott Brown, special agent in charge of HSI Phoenix, presented the relics to Mexican Consul General Ambassador Ricardo Santana and Jose Luis Perea, director of the Mexican Institute for Anthropology and History (INAH) in Sonora, Mexico. The Mexican officials accepted the relics on behalf of the people of Mexico.

“The cultural significance of artefacts from regions around the world extends beyond any monetary value,” said SAC Brown. “The pieces, like those discovered, are fragments of history; and it is an honour to return them to their rightful home country. HSI fully supports the importance of antiquities and cultural property, and it is through these repatriations that new generations are able to experience a part of their nation’s story.”

The HSI Phoenix case began Oct. 8, 2013, when special agents were contacted by a representative of the Chandler Historical Society regarding multiple suspected pre-Columbian Chinesco-Western pottery figures with origins as far back as 100 B.C., which were in the possession of the City of Chandler Museum.

HSI special agents promptly met with the museum’s director who turned over 10 Shaft Tomb artefacts for further review and investigation. Through archaeological expert analysis, the authenticity of these artefacts was confirmed as being more than 1,500 years old and originating from Mexico.

HSI special agents met with the Mexican consulate general of Nogales, director of archaeology in Sonora, Mexico, chief archaeologist for the Cerro de Trincheras zone to view the artefacts, which were authenticated as historically significant artefacts originating from Mexico.

Results of this meeting confirmed the 10 ceramic figurines to be Shaft Tomb artefacts believed to accompany deceased individuals during the last rite of passage circa 100 B.C. to 500 A.D. from the geographic regions of Nayarit, Jalisco, and Colima, Mexico. The archaeological experts estimated the value of the artefacts between $26,100 and $45,700.

The HSI Nogales case began in October 2012, after HSI special agents were contacted by U.S. Customs and Border Protection (CBP) regarding numerous suspected Pre-Columbian artefacts that were declared by two Mexican citizens who presented themselves for entry into the United States from Mexico via the Mariposa Port of Entry in Nogales.

HSI Nogales took custody of 267 artefacts. The items detained included arrowheads, axe heads, hammerheads, spearheads, and small stone carvings. Archaeological expert analysis subsequently confirmed the authenticity of the artefacts as being between 1,000 and 5,000 years old and of significant cultural value.

In March 2013, HSI Hermosillo representatives contacted INAH in Sonora to arrange a meeting with HSI Nogales at the CBP Nogales administrative offices to conduct a thorough examination of the detained artefacts.

The three INAH research professor archaeologists viewed the artefacts and concluded that the 267 individual pieces were pre-Hispanic (aka pre-Columbian) cultural artefacts of Mexican origin from Northwest Mexico. INAH appraised the artefacts at over $124,000.

HSI concluded that all the seized pieces were imported into the United States contrary to law pursuant to the United Nations Educational, Scientific and Cultural Organization (UNESCO) Convention of 1970 and the Cultural Property Implementation Act, and therefore were to be returned to their proper home of Mexico.

U.S. Consul General in Nogales Laura Biedebach underscored, “The United States government is committed to combating the theft and trafficking of cultural heritage and to preserving and protecting it where it is found. We will continue to cooperate across agencies and borders to ensure that our citizens can enjoy their cultural heritage. We have much work to do to preserve our history for the next generation, but we are in this together and proud to be your partners.”

“This repatriation comes at an opportune time, in the year of a very significant commemoration for Mexico, the 500th anniversary of the taking of Tenochtitlan, which was a heartrending encounter between the cultural universes of Western Europe and America, said INAH Director Jose Luis Perea. “This event allows us to deeply recognize the pre-Hispanic cultures of Mexico, as well as the resistance and presence of its contemporary indigenous peoples.”

HSI is the investigative arm for the U.S. Department of Homeland Security and plays a leading role in criminal investigations that involve the illicit distribution of cultural property, as well as the illegal trafficking of artwork, specializing in recovering works that have been reported lost or stolen. HSI’s International Operations, through its 80 offices in 53 countries, works closely with foreign governments to conduct joint investigations.

Despite increasingly aggressive enforcement efforts to prevent the theft of cultural heritage and other antiquities, the illicit movement of such items across international borders continues to challenge global law enforcement efforts to reduce the trafficking of such property. Trafficking in antiquities is estimated to be a multi-billion dollar transnational criminal enterprise.

HSI is committed to pursuing a strategy to combat transnational organized crime related to the illicit trafficking of cultural artefacts by targeting high priority organizations and strengthening international law enforcement partnerships.

The public, government and private institutions often aid HSI in identifying, investigating and prosecuting illicitly trafficked cultural property. If you have information about the illicit trade of cultural property or art, call the ICE Tip Line at 1-866-DHS-2-ICE or report tips online.

World’s biggest pyramid isn’t in Egypt – it’s hidden under a hill in Mexico

While Egypt’s Great Pyramid of Giza is by far the most talked-about pyramid in the world, it isn’t the biggest by a long shot. That title goes to the Great Pyramid of Cholula – an ancient Aztec temple in Puebla, Mexico with a base four times larger than Giza’s, and nearly twice the volume.

Why is the world’s biggest pyramid so often overlooked? It could be because that gigantic structure is actually hidden beneath layers of dirt, making it look more like a natural mountain than a place of worship.

In fact, it looks so much like a mountain, that famed Spanish explorer Hernán Cortés completely missed it, and unwittingly built a church right on top of it, as you can see in the image above.

To understand how awesome the Great Pyramid of Cholula is, we must jump back to well before Cortés and his army planted a symbol of Christianity on its peak.

Known as Tlachihualtepetl (meaning “man-made mountain”), the origins of the pyramid are a little sketchy, though the general consensus is that it was built around 300 BC by many different communities to honour the ancient god Quetzalcoatl.

As Zaria Gorvett reports for the BBC, the pyramid was likely constructed with adobe – a type of brick made of out of baked mud – and features six layers built on top of each over many generations. Each time a layer was completed, construction was picked back up by a new group of workers.

This incremental growth is what allowed the Great Pyramid of Cholula to get so big. With a base of 450 by 450 metres (1,480 by 1,480 feet), it’s four times the size of the Great Pyramid of Giza.

In fact, at roughly 66 metres (217 feet) tall, the pyramid’s total volume is about 4.45 million cubic metres (157 million cubic feet), while the Great Pyramid of Giza’s volume is just 2.5 million cubic metres (88.2 million cubic feet).

The Great Pyramid of Giza is taller, though, at 146 metres (481 feet) high. The ancient Aztecs most likely used the Great Pyramid of Cholula as a place of worship for around 1,000 years before moving to a new, smaller location nearby.

Before it was replaced by newer structures, it was painstakingly decorated in red, black, and yellow insects. But without maintenance, the mud bricks were left to do what mud does in humid climates – provide nutrients to all kinds of tropical greenery.

“It was abandoned sometime in the 7th or 8th Century CE,” archaeologist David Carballo from Boston University told Gorvett at the BBC. “The Choluteca had a newer pyramid-temple located nearby, which the Spaniards destroyed.”

When Cortés and his men arrived in Cholula in October 1519, some 1,800 years after the pyramid was constructed, they massacred around  3,000 people in a single hour – 10 per cent of entire city’s population – and levelled many of their religious structures.

But they never touched the pyramid, because they never found it. In 1594, after settling in the city and claiming it for their own, they built a church – La Iglesia de Nuestra Señora de Los Remedios (Our Lady of Remedies Church), on top of the hidden pyramid mountain. 

It’s unclear if the Aztecs knew the mud bricks would encourage things to grow all over it and eventually bury the entire structure, but the fact that it looks more like a hill than a pyramid is probably the only reason it still survives today.

And just as well, because according to the BBC, not only is it the world’s largest pyramid, it retains the title of the largest monument ever constructed anywhere on Earth, by any civilisation, to this day.

The pyramid wasn’t discovered until the early 1900s when locals started to build a psychiatric ward nearby. By the 1930s, archaeologists started to uncover it, creating a series of tunnels stretching 8 kilometres (5 miles) in length to give them access.

Now, over 2,300 years after its initial construction, the site has become a tourist destination.

Hopefully, as our ability to study important sites using non-invasive tools continues to improve, archaeologists will gain a better understanding of how the structure was built, by whom, and how it came to look so much like a mountain.  

The secret cave lies hidden below the enormous ‘Moon Pyramid’

An underground cave hidden under a Mexican pyramid provides clues about Teotihuacan’s urban architecture, one of the oldest and most vibrant cities of ancient times. Located about 80 kilometres outside present-day Mexico City, Teotihuacan peaked long before the Aztecs in AD 300-650. Three monumental pyramids were arranged along the 2.4-kilometre ‘Path of the Dead’ in the area.

Two of the pyramids had already been known to overlie caves and tunnels, which were excavated by Teotihuacanos to procure building materials, and were later rebuilt for activities such as astronomical observation, veneration of death and the enthronement of rulers.

Denisse Argote at the National Institute of Anthropology and History in Mexico City and her colleagues measured the electrical resistance of the ground beneath the third structure, the 43-meter-high Moon Pyramid.

They discovered a partially filled cavern about 15 meters underneath the edifice.

Unlike the other caves, this one seems to have formed naturally. Argote and her colleagues think the first settlers of Teotihuacan might have chosen it to be the focal point from which the rest of the city was planned.

Hard Science Unlocks Secrets of Teotihuacan’s Pyramid of the Moon

Previous archaeological digs at Teotihuacan have revealed a series of man-made tunnels beneath the Pyramids of the Sun and of Quetzalcoatl, the latter of which is also called the Temple of the Feathered-Serpent.

These had mostly been excavated for construction materials in upper structures, and according to a report in Heritage Daily, these tunnels were later “repurposed for astronomical observations and for venerating death in the underworld.”

The team of scientists applied ERT and ANT surveys, which are non-invasive geophysical techniques analyzing the electrical resistance of the ground beneath the structure.

They identified a natural void beneath the Pyramid of the Moon and a partially filled cavern at a depth of 15 meters (49 ft.) Contrasting with the man-made tunnels beneath the Pyramid of the Sun and the Pyramid of Quetzalcoatl at Teotihuacan, the researchers believe that the cave under the Pyramid of the Moon “formed naturally,” and had been a focal point for the early settlers, in turn, influencing how the city was planned out.

Otherworldly Architectural Town Planning

With the placement of the pyramid at the end of the Avenue of the Dead, at the foot of Cerro Gordo, shaped to reflect the contours of these mountains, the researchers theorize that it was “symbolic of a connection between the avenue and the watery underworld, whereas the mountain serves as an anchor to the earth.” They said the impact of this discovery opens a discussion about the original planning of Teotihuacan’s urban design.

The first human establishment in the area dates back to around 600 BC when farmers began tilling the Teotihuacan Valley, which at that time had a total population of about 6,000 inhabitants.

However, due to the development of successful agricultural technologies, from 100 BC to 750 AD, Teotihuacan morphed into a huge urban and administrative centre with cultural influences throughout Mesoamerica.

Mapping the Ancient Underworld

Period III, from 350 to 650 AD, the so-called classical period of Teotihuacan, had an estimated 125,000 inhabitants. At that time it was one of the largest cities of the ancient world – with over 2,000 buildings in an 18 square kilometre (6.95 sq. mile) area.

This period saw the massive reconstruction of monuments; including the decorating of the Temple of the Feathered Serpent which dates back to an earlier period.

Period IV, between 650 and 750 AD, marks the end of Teotihuacan as a major power in Mesoamerica. The remains of the homes of the city’s elites, which line the Avenue of the Dead, bear burn marks which lead archaeologists to hypothesize that the city experienced waves of violent social unrest that brought about the city’s decline.

What the newly discovered cave system essentially does is answer the question “why” the first settlers stopped here and started building precisely where they did, and not say 10 miles east or five miles south.

The cave beneath the pyramid suggests that people revered this natural access to the underworld so much that around it they built one of the most influential and biggest cities of the ancient world.

And the remains of that vast crumbling ancient city, which was aligned with the Sun, moon, and stars, it would seem, is a 1:1 map of the underworld – with the Avenue of the Dead acting as the main channel to the other side.

Geologists Map Secret Tunnel And Chamber Found Beneath Aztec Pyramid

“Teotihuacan, translated from the Aztec language as “birthplace of the gods,” or “a place where gods were born,” was a very important religious and cultural center during the Aztec empire.

Less than a decade ago, archaeologists uncovered an almost 60-foot Vertical shaft under the Avenue of the Dead.

Excavation of the tunnels beneath the Avenue was not possible, but in 2017 a team of geologists used electrical resistivity mapping to map the underground beneath the Avenue of the Dead.

This archaeological site in modern-day Mexico is famous for its broad central “Avenue of the Dead,” surrounded by a dozen pyramids and platforms. The 150 feet high Pyramid of the Moon was built in successive phases and construction completed between 200 and 250 CE. The nearby Pyramid of the Sun is even higher at 216 feet.

Excavation revealed a system of tunnels and chambers. Human remains and diverse objects made from green obsidian, a type of volcanic rock used in religious rituals, were recovered.

The extent of this tunnel-system remains uncertain to this day. Archaeologists suspected that the tunnels follow the pattern of the streets and pyramids on the surface.

As excavation of the complete site was not possible, in 2017 a team of geologists used electrical resistivity imaging to map the underground beneath the Avenue of the Dead.

Electrical resistivity imaging is a geophysical technique used also on other archaeological sites to map the composition of the underground, revealing large subterranean cavities or the presence of groundwater.

The researchers discovered a tunnel at a depth of 26 feet, that starting from the center of the avenue runs to 49 feet in diameter large cavity hidden beneath the Pyramid of the Moon.

The age and the use of this network of tunnels and chambers remain uncertain. The walls of the excavated tunnels were covered with pyrite powder.

Visitors would see the grains of this yellow mineral glitter in the light of torches, an effect resembling the stars of the celestial sphere. It was suggested that the tunnel-system acted as a symbolic gateway, connecting the sky with the underworld, and played an important role in religious rites.

The origin of the tunnel-system – and the city – are still being studied.  Centuries later, the Aztecs built some towns on the site of the ancient city, but it’s not yet clear if they used the preexisting tunnel-system.

Around 300 CE, the tunnels appear to have been sealed off and nobody knows why or what the chamber may hide.

The Rome of America: What Lies Under Teotihuacan? – The Real City of the Gods

It was one of the first large cities in the Western Hemisphere, the Huge. And its origins are a mystery.  About a thousand years before the gradual arrival in central Mexico of the Nahuatl-speaking Aztec, it was built by hand. But it was the Aztec, descending on the abandoned site, no doubt falling awestruck by what they saw, who gave its current name: Teotihuacan.

According to George Cowgill, an archaeologist at Arizona State University and a National Geographic Society grantee—Teotihuacan, a famous archaeological site less than 30 miles (50 kilometres) from Mexico City, Teotihuacan reached its zenith about 100 B.C. And A.D. 650.

It covered 8 square miles (21 square kilometres) and supported a population of a hundred thousand.

“It was the largest city anywhere in the Western Hemisphere before the 1400s,” Cowgill says. “It had thousands of residential compounds and scores of pyramid-temples … comparable to the largest pyramids of Egypt.”

Oddly, Teotihuacan, which contains a massive central road (the Street of the Dead) and buildings including the Temple of the Sun and the Temple of the Moon, has no military structures—though experts say the military and cultural wake of Teotihuacan was heavily felt throughout the region.

Who Built It?

Cowgill says the site’s visible surface remains have all been mapped in detail. But only some portions have been excavated.

Scholars once pointed to the Toltec culture. Others note that the Toltec peaked far later than Teotihuacan’s zenith, undermining that theory. Some scholars say the Totonac culture was responsible.

No matter its principal builders, evidence shows that Teotihuacan hosted a patchwork of cultures including the Maya, Mixtec, and Zapotec.

One theory says an erupting volcano forced a wave of immigrants into the Teotihuacan valley and that those refugees either built or bolstered the city.

The main excavations, performed by Professors Saburo Sugiyama of Aichi Prefectural University in Japan and Rubén Cabrera, a Mexican archaeologist, have been at the Pyramid of the Moon.

It was there, beneath layers of dirt and stone, that researchers realized the awe-inspiring craftsmanship of Teotihuacan’s architects was matched by a cultural penchant for brutality and human and animal sacrifice.

Inside the temple, researchers found buried animals and bodies, with heads that had been lobbed off, all thought to be offerings to gods or sanctification for successive layers of the pyramid as it was built.

Since 2003, archaeologist Sergio Gomez has been working to access new parts of the complex and has only recently reached the end of a tunnel that could hold a king’s tomb.

It’s unclear why Teotihuacan collapsed; one theory is that poorer classes carried out an internal uprising against the elite.

For Cowgill, who says more studies are needed to understand the lives of the poorer classes that inhabited Teotihuacan, the mystery lies not as much in who built the city or in why it fell.

“Rather than asking why Teotihuacan collapsed, it is more interesting to ask why it lasted so long,” he says. “What were the social, political, and religious practices that provided such stability?”

Golden Eagle Sculpture Unearthed in Aztec Temple

According to a statement released by Mexico’s National Institute of Anthropology and History (INAH), archaeologists led by Rodolfo Aguilar Tapia have uncovered a bas-relief sculpture of a golden eagle in the floor of the Aztec chapel dedicated to Huitzilopochtli at the Templo Mayor.

The well-preserved floor surface was covered during an expansion of the temple before the arrival of the Spanish in Tenochtitlan in the sixteenth century, Tapia explained.

“From what we have seen through photographs, it is a very beautiful piece that shows the great secrets that the Templo Mayor of Mexico Tenochtitlan has yet to reveal to us. I want to extend my appreciation to the INAH archaeologists who collaborate in this space, since, thanks to their effort and dedication, we can continue to recover our history and our memory.

Due to the health contingency, the fieldwork has had to be postponed, however, it is clear that there is also an important work of research and academic reflection that has not stopped “, said the Secretary of Culture, Alejandra Frausto Guerrero, about this notable finding.

Although it was in February 2020 when a multidisciplinary team concluded the release and cleaning of this itzcuauhtli , a Nahua voice that means “obsidian eagle”, and with which the Mexica referred to the golden eagle ( Aquila chrysaetos canadensis ), it is now, when his investigation in the cabinet has been deepened, the finding is made known.

Carved on red tezontle and with dimensions of 1.06 meters long by 70 centimetres wide, this bas-relief is the largest in a set of 67 similar elements found so far in the Templo Mayor.

According to specialists, the relevance of the sculpture is denoted not only by its size and finish but also by its location, at the foot of the most important building for the Mexica and in the central axis that crosses the ‘chapel’ of Huitzilopochtli and the monumental sculpture of the goddess Coyolxauhqui. It is also close to Cuauhxicalco, a circular building whose name translates as “place of the eagle’s gourd”, where, according to 16th-century documents, the ritual cremations of the Tenochca rulers were carried out.

Regarding the discovery of the bas-relief, the archaeologist assigned to the PTM, Rodolfo Aguilar Tapia, who investigated the piece together with the interns in archaeology Mary Laidy Hernández Ramírez and Karina López Hernández; and in physical anthropology, Jacqueline Castro Irineo, from the National School of Anthropology and History, reported that it was verified during the ninth field season of the PTM.

This season, directed by the head of the Project, the archaeologist Leonardo López Luján, has focused on exploring under the ‘liga bridge’ that connects the streets of Guatemala and Argentina, wherein pre-Hispanic times the west plaza of the Sacred Precinct was located of Mexico-Tenochtitlan. The sculptural carving was part of a floor of that space, which would have been in use during the government of Motecuhzoma Ilhuicamina, between the years 1440 and 1469 of our era.

“This floor is unique in the entire Templo Mayor as it contains bas-reliefs that allude to the dual conception of the building. On the south side, where we are exploring, there are elements like this eagle, linked to the mythical cycle of the birth of Huitzilopochtli; while to the north, the bas-reliefs located earlier —the first in 1900 by Leopoldo Batres, and the later by the PTM and the Urban Archeology Program (PAU) – contain representations associated with Tláloc, the water cycle and the regeneration of corn “.

Aguilar Tapia specifies that thanks to the work carried out by archaeologists Eduardo Matos Moctezuma and Leonardo López Luján, today there is a defined stratigraphic correspondence, which allows researchers to know in which construction stage of the Templo Mayor the findings are located, and at what time belong the same.

Thus, he exemplifies, when the exploration at the aforementioned intersection began, the floor that the archaeologists saw was from Stage VI of the Templo Mayor, corresponding to the government of Ahuítzotl between 1486 and 1502, while now, after meticulous excavations, specialists have managed to reach Stage IV-a, that is, they have gone back in time to the 1440s and to the period of government of Motecuhzoma I.

The aforementioned plaza floor was covered since pre-Hispanic times during the expansion of the Templo Mayor. “That is why it has a good state of conservation,” says the researcher, noting that “it is an element that was never seen by the Spanish.”

The symbolism of the golden eagle

The pause in the fieldwork that the COVID-19 pandemic brought with it, allowed the PTM researchers to carry out the investigation of various elements, including the bas-relief. Among other aspects, the iconographic representations that exist of the golden eagle in historical sources such as the codices were studied, in order to correlate them with the sculpture discovered at the foot of the Templo Mayor.

One of those representations, Aguilar Tapia points out, is in Plate 50 of the Codex Borgia, where a golden eagle is shown posing on top of a mesquite tree, a tree that rises from a stark deity. “The interesting thing is that this image is iconographically very similar to the bas-relief that we find in the field, in both representations the feathers end in the shape of sacrificial knives, which allude to the Nahua name of the bird: obsidian eagle.”

For the Mexica, this bird of prey was closely related to war and sacrifice, while it was considered a nahual of the sun and, therefore, also of its tutelary god, Huitzilopochtli.

In the incoming seasons of the PTM field, the researcher concludes, the actions will focus on completing the exploration of the floor where the bas-relief is located to look for more others and then, with extreme care, temporarily remove them and be able to investigate under them in search of offerings or other architectural elements. “After all this exploratory process, with the support of restoration specialists, we will place each bas-relief in its precise place”, he concludes.

Similar elements could also be found when the excavations around Cuauhxicalco are resumed. The intention of the PTM is that, after its investigation, the bas-reliefs can be shown to the public in their original position: at the west foot of the Templo Mayor.

Experts find 2,000 ruin sites near the Maya train route project in Mexico

Archaeologists in Mexico have provided a study from specialists that cites have more than 2,000 pre-Hispanic ruins or clusters of artifacts along the planned path of the president’s controversial “Maya Train” project on the Yucatan peninsula.

The discovery of sites using LiDAR elevation mapping technology could slow down the already disputed project, which opponents contend also threatens indigenous communities and water supplies.

The laser elevation data showed a total of 2,187 “archaeological monuments” along 277 miles (366 kilometers) of the proposed route, about one-quarter of the total planned track. Experts already knew about the existence of some of the sites, but some are new.

The term “monuments” can mean many things, ranging from the remains of a pre-Hispanic Maya home, or carved stones, all the way up to remains of temple platforms.

It was not clear how many of each type of artifact was detected, but Mexico’s National Institute of Anthropology and History said at least 91 were large-scale structures like plazas, pyramid or temple platforms.

Mayan houses were generally relatively insubstantial, with stone bases topped by thatch and wooden structures of which little remains.

The institute said in a statement that the builders of the train would have to take “specific measures” to avoid damaging the artifacts, but did not say whether that meant parts would have to be re-routed.

In July, President Andres Manuel Lopez Obrador inaugurated the start of construction on the “Maya Train,” a pet project of his that would run some 950 miles (about 1,500 kilometers) in a rough loop around Yucatan.

The train is intended to connect Caribbean beach resorts to the peninsula’s interior, with largely indigenous populations and ruin sites, in a bid to stimulate economic development around its 15 stations. The government says it will cost as much as $6.8 billion, but others say it will be much more.

Critics say Lopez Obrador rammed through the project without adequate study of its effects on the environment, underground sinkhole caves known as cenotes, and ruin sites.

Some stretches of the route already have tracks, and the institute said some artifacts had already been disturbed by railway construction decades ago.

But other stretches are to push through sensitive jungle terrain, though they will parallel existing roads or transmission lines. Even where an old railway line exists, the project would imply updating tracks and building new stations.

Some Mayan communities have filed court challenges against the project, arguing that it will cause environmental damage. They also say they were not adequately consulted about it or they will not share in its benefits.

LiDAR, which stands for Light Detection and Ranging, involves shooting a pulsed laser at the ground to get a high-resolution, detailed image of the surface, even through dense vegetation.

The Mayas formed a sprawling empire of city-states across the Yucatan and Central America between 2,000 B.C. and A.D. 900, and their descendants still live on the peninsula.