30 Fascinating and Mysterious Archaeological Discoveries

Archaeological discoveries are fascinating because they provide a glimpse into the everyday lives of past civilizations. And archaeological discoveries with a mystery surrounding them are particularly captivating.

From a mysterious manuscript written in a different language to Californian geoglyphs, here are 30 archaeological discoveries that simply cannot be explained.

Stone Spheres in Costa Rica

Huge stone spheres dot southern Costa Rica’s Diquis Delta. Locally, they are called Las Bolas (the balls). There are around 300 stone spheres, with the largest weighing 16 tons and measuring eight feet in diameter. Created by indigenous people in Costa Rica, the spheres were preserved from the looting that occurred on other Costa Rican archaeological sites because they were buried by thick layers of sediment.

Photo Courtesy: Wikimedia Commons

Although the earliest reports of the stones come from the 19th century, they were virtually unknown until the United Fruit Company cleared land in southern Costa Rica for banana plantations in 1940. Scientists believe that the stone spheres were first created around 600 A.D., but the majority of them date to after 1,000 A.D.

Only a handful of the spheres remain in their original location. UNESCO put the spheres on its World Heritage list and describes them as “distinctive for their perfection, number, size and density, and placement in original locations.”

The Nazca Lines of Peru

Giant designs of plants, animals, lines and shapes are etched into the ground in Peru. Called geoglyphs, the ancient Nazca people created them. The 2,000-year-old geoglyphs are located 250 miles south of Lima, and they are best viewed from the air. They consist of more than 800 straight lines, 300 geometric designs and about 70 animals and plants.

Photo Courtesy: Ray_LAC/Flickr

Designated a UNESCO World Heritage Site in 1994, they still pose a mystery to experts. Although research on the geoglyphs is ongoing, researchers tend to think that the Nazca used them in conjunction with their rituals. Researchers point to the geoglyphs that depict animals as proof that some of them symbolize water or rain. 

The Blythe Intaglios: America’s Nazca Lines

Etched in the ground of the California desert are intaglios, or geoglyphs, that depict large human figures made 450 to 2,000 years ago. Known as the Blythe Intaglios, the biggest of the figures are more than 170 feet long. They remained undiscovered until 1932, when pilot George Palmer noticed them while flying from Las Vegas, Nevada to Blythe, California.

Photo Courtesy: Ron’s Log/Wikipedia

Like the Nazca Lines of Peru, researchers do not know what purpose they served. Some researchers think they were made by the Mohave and Quechan tribes and represent Mastamho, the deity the tribes believed was the creator. Other researchers think the figures are representative of powerful people in a native tribe.

One of the reasons it’s so hard for researchers to determine exactly when they were made is because most of the human figures are next to what seem to be horses. Horses became extinct in the U.S. about 10,000 years ago, but when the Spanish arrived in California in the mid-16th century, they brought horses with them.

Gobekli Tepe

When large pillars were first discovered in 1994 in a rural area of Southeastern Turkey called Gobekli Tepe, some claimed it was the biblical Garden of Eden. The site is set atop a hill and consists of mostly oval and circular-shaped structures. Each pillar weighs 40 to 60 tons, is 9.8 to 19.6 feet tall and 33 to 98 feet in diameter with floors made of burnt lime.

Photo Courtesy: Liangtai Lin/Flickr

Excavations have taken place since the discovery in 1994, but excavators estimate they have only uncovered about five percent of the site. What excavators believe is that there might have been roofs on top of the pillars. They also think the people living at the site buried the monuments around 8,000 B.C. But what researchers don’t know is why they buried the site. Excavators surmise that the monuments were probably utilized in funeral rituals. 

Underground City in Cappadocia, Turkey

A region in central Turkey called Cappadocia is renowned for having underground houses, churches and cities. In 1963, a man renovating his home discovered a secret passage leading to an underground city called Derinkuyu. Construction workers discovered another underground city similar to Derinkuyu in 2013 while demolishing houses around a Byzantine-era castle in Nevşehir. Like Derinkuyu, the site contains water channels and air shafts.

Photo Courtesy: MusikAnimal/Wikipedia

Archaeologists think the site might even be bigger than Derinkuyu, which could house 20,000 people. However, the archaeologist overseeing the excavation of the site, Murat Gülyaz, director of the Nevşehir Museum, told National Geographic: “As of now, it is not possible to say. But given the city’s location, defenses and proximity to a water supply, it is highly likely that it spans a very large area.”

Divination Shrines in Gegharot, Armenia

Archaeologists discovered three shrines during excavations in 2003 to 2011 in Gegharot, Armenia. The shrines, which are about 3,300 years old and date back to the Bronze age, are located on a hilltop fortress. Each shrine has a room with a clay basin containing ceramic vessels and ash. Artifacts were also discovered, including: animal bones, clay idols, drinking vessels and grain grinding tools used to make impressions in dough.

Photo Courtesy: Cornell University

What’s mysterious about the shrines? The people who constructed them. A nameless people began to build strongholds around 1,500 B.C. along the Tsaghkahovit Plain, which had been sparsely populated prior. 

The Copper Scroll Treasure

An archaeologist discovered an ancient copper scroll in 1952 at Qumran, located in the present day West Bank in the Palestinian territories. Qumran’s archaeological ruins date back to the Iron Age, as it’s also the site where Bedouin found the famed Dead Sea Scrolls. But unlike the Dead Sea Scrolls, the Copper Scroll is not a copy of biblical books. It lists valuable items, including gold and silver, and is written on copper and not papyrus or parchment.

Photo Courtesy: Qumran Copper Scroll/Wikimedia Commons

The scroll dates back nearly 2,000 years ago when Romans had control of the Qumran settlement. During the Hellenistic period (about 134 to 104 B.C.), the Essene Jewish sect settled at Qumran. Researchers think the scroll may describe treasure locals hid to keep away from Roman forces during a time of revolt. 

The Golan Structure

A plane first noticed the Golan structure while surveying the Golan Heights in 1968. It consists of an outermost ring that is 500 feet wide and about 5,000 years old. There is also a labyrinthine structure of basalt rocks weighing about 40,000 tons with a large burial chamber in the middle. The structure is called Rujm el-Hiri in Arabic, which means “the stone heap of the wildcats,” and Gilgal Refaim in Hebrew, meaning the wheel of giants.

Photo Courtesy: Michael Homan/Flickr

Many have compared it to well-known archaeological finds like Stonehenge in England and the pyramids in Egypt. Dr. Michael Freikman of Hebrew University completed his doctorate on the structure. He told Israeli newspaper, Haaretz that building it would have required as many as a million workdays and 100 laborers, with construction taking around 25 years. 

America’s Stonehenge

An archaeological site exists in Salem, New Hampshire originally called Mystery Hill. It consists of a one-acre grouping of stone-structures and rocks. The site was first discovered and explored in 1937 by William Goodwin, who bought the land where the site is located. Whether it is truly ancient or not remains a mystery.

Photo Courtesy: NikiSublime/Flickr

Some claim that through carbon-dating, archaeologists have found some of the site dates back to 2,000 B.C. However, others claim the site was built by English colonial settlers. Others think a 19th-century shoemaker constructed the site. David Starbuck, a Plymouth State University archaeologist, wrote in his 2006 book “The Archaeology of New Hampshire: Exploring 10,000 Years in the Granite State” that the site is “unquestionably provocative, puzzling and, above all, controversial.” 

Casa Grande Ruins National Monument

The ruins of a four-story building sit in Coolidge, Arizona. Known as the Casa Grande Ruins, the ancient Sonoran Desert civilization, the ancestors of the O’Odham, Hopi and Zuni people built it using adobe. The structure is 60 feet tall by 40 feet wide at the base. Experts believe the complex included a few other adobe structures, including a ball court, and had a wall surrounding it.

Photo Courtesy: Greg Hume/Wikipedia

The name, which means the “great house” in Spanish, comes from journal entries by Padre Eusebio Francisco Kino who visited the site in 1694. Casa Grande is “one of the largest prehistoric structures ever built in North America,” according to the National Park Service.

Antikythera Mechanism

More than a hundred years ago, an artifact was discovered in a sunken Greek cargo ship dating back at least 2,000 years to the end of the 2nd century. Known as the Antikythera Mechanism, the circular bronze device has a design of interlocking gears and characters. Although its use is not fully known, it is thought to be a type of astronomical calculating device.

Photo Courtesy: Gary Todd/Flickr

Using x-ray imaging, researchers discovered the device seems to imitate the motions of the heavens, and with it someone could track the paths of the planets, the moon and the sun. One researcher even called it “an ancient Greek computer.” 

Malta’s Cart Ruts

A prehistoric site in Siġġiewi, Malta, contains mysterious deep tracks carved into the area’s limestone called cart ruts. There are numerous cart ruts in a place named Clapham Junction, or Misrah Ghar il-Kbir, as the Maltese call it. Archaeologist David Trump, who has excavated Malta since 1954, calls the cart ruts “one of the most intriguing problems in Maltese archaeology.”

Photo Courtesy: Ronny Siegel/Wikimedia Commons

Researchers don’t know how old they are or what purpose they served. Some experts think the cart ruts are millions of years old, while others believe they may be a relic from stone age agriculture. Still, others think they were created by heavy carts that moved tons of stones, but that is an unlikely explanation as the tracks go up steep slopes and continue to cliffs. 

Voynich Manuscript

A medieval book nearly 250 pages long is considered to be the “world’s most mysterious manuscript.” A citizen of Prague named Georgius Barschius mentioned the manuscript in a letter in 1639, explaining he had a book written in an unknown language that was illustrated with pictures. The book changed hands many times until a Polish-American antique bookseller, Wilfrid M. Voynich, acquired it in 1912.

Photo Courtesy: Wikimedia Commons

The manuscript has been in Yale University’s Beinecke Library since 1969 where it is officially called MS 408, but better known as the Voynich Manuscript. Researchers have tried to decipher the manuscript for over 300 hundred years, but it still remains a mystery. Based on the illustrations, researchers have determined there are six sections: an herbal section, an astronomical section, cosmological section, biological section, pharmaceutical section and a recipes section. 


A group of mounds in Pakistan called Mohenjo-Daro is located on the banks of the Indus River in the northern Sindh province in Southern Pakistan. First excavated by archaeologists in 1911, the site was constructed about 2,500 B.C. The ruins represent a major center of the Indus civilization, what was once the largest city of the ancient civilization.

Photo Courtesy: Saqib Qayyum/Wikimedia Commons

Designated a UNESCO World Heritage site in 1980, researchers still don’t know much about the people who lived there. “It’s pretty faceless,” Indus expert Gregory Possehl of the University of Pennsylvania told National Geographic. The ruins are on elevated ground and contain no evidence of royalty, leading researchers to conclude the ancient city was a city-state, likely a capital city, perhaps with elected officials. 

Underwater Monument of Yonaguni

Off the Japanese coast, there’s an underwater monolith some call “Japan’s Atlantis.” The submerged structure looks resembles a huge pyramid, and was discovered by a scuba diver named Kihachiro Aratake in 1987. Soon after his find, researchers began to explore the underwater monument. Since then, it has become a tourist attraction that attracts divers willing to deal with strong currents.

Photo Courtesy: Vincent Lou/Wikipedia

What’s so interesting about the Yonaguni monument (what it has been dubbed), is that all the details point to human construction, such as pillars, a 33 feet wide wall, a road and a stone column. Despite all these details, there are still those who believe it is a natural formation. Others believe it was once part of an ancient city and is a human-built stepped pyramid. 

Sandby Borg Massacre Site

Archaeologists conducting excavations on Öland island off the coast of Sweden (in the Baltic Sea) were surprised to find skeleton feet in the doorway of the remains of a fifth-century house. After digging up the rest of the body, they encountered evidence that the person had been murdered. Next to the skeleton, they found another one. Additionally, they kept finding skeletons in nearby remains of houses.

Photo Courtesy: Wikimedia Commons

Researchers identified 26 people who were murdered about 1,500 years ago in a fort called Sandby Borg ringfort. Some of the bodies had goat and sheep teeth stuck in their mouths. Researchers say the inhabitants of the fort were murdered violently and quickly. The perpetrators of the massacre are unknown. 

A City Built on Corals

Near the Micronesian island of Pohnpei exists the ruins of a city first inhabited during medieval times. Designated a National Historic Landmark, the city Nan Madol (meaning ‘within the intervals’) is located on a coral reef in a lagoon on the Temwen Island. It was inhabited for 500 years, from 1200 to 1700, and was a fortress, marketplace, religious center and enclave for royals.

Photo Courtesy: National Park Service

It was also the high seat of government for Pohnpei. The U.S. National Park Service describes it as a “hidden gem of Polynesian history and culture.” Nan Madol features basalt stones that were carved and stacked in a crisscross pattern to form walls around the 130 buildings of the city. Some of the stones weigh 100,000 pounds. The largest building is a royal temple with 25-foot walls surrounding it.

It remains a mystery how the Pohnpeians put the stones into the lagoon as they lacked concrete, binding agents or even modern diving equipment. 

The Amazing Sacsayhuaman Walls of Peru

Three stone walls located near Cuzco, Peru, amazed the Spanish conquistadors who landed in the area. The three walls are about 1,110 feet in length by 19 feet in height, built from limestone blocks weighing about 300 tons each. Called Sacsayhuaman (meaning ‘royal eagle’), it was once an Incan fortress-temple complex and is still used for reenactments of ceremonies inspired by the Inca. It is the largest structure the Incas built.

Photo Courtesy: Diego Delso/Wikipedia

Researchers are not sure how the Inca built the three large walls. They lacked access to draft animals and had not yet invented the level or the wheel, making this task nearly impossible. Some of the rocks used to build the wall are very close together, so close that it’s not possible to put a piece of paper between them. To build just one wall would have taken months, yet these walls have proven to be resilient and earthquake-proof.

The Cochno Stone

In 2016, archaeologists excavated a slab of stone 5,000 years old in Glasgow, Scotland, then reburied it. The stone, known as the Cochno Stone, is 43 feet by 26 feet with swirling designs called “cup and ring marks” that have been found at prehistoric sites in other places in the world.

Photo Courtesy: Canmore: National Record of the Historic Environment

The stone slab may be ancient artwork, according to archaeologist Kenny Brophy from the University of Glasgow. First unearthed in 1887, archaeologists buried the stone slab in 1965 to keep it from being vandalized. Before reburying it, researchers used 3D imaging to create a digital record of the Cochno Stone.

Researchers still do not know the meaning of the stone slab, but hope the information gathered in 2016 will help them learn more about its purpose and the people who created it. 

Great Serpent Mound of Ohio

In a rural area in Southwestern Ohio exists the biggest representation of a serpent in the world. Measuring roughly 1,300 feet long and one to three feet tall, the serpent is designed in such a way that the tail is west and the head is east. The serpent mound is a National Historic Landmark.

Photo Courtesy: Eric Ewing/Wikipedia

Archaeologists are still unsure as to what the serpent mound represents. When 19th-century archaeologist Frederic Ward Putnam excavated the site in the late 19th century, he did not find any artifacts the could help researchers figure out which culture was responsible for the mound. There are nearby Adena burial grounds, so archaeologists after Putnam attributed the serpent mound to the Adena culture, which was active in the area from 800 B.C to 100 A.D. 

Easter Island Heads

The Easter Island heads are some of the most recognizable stone formations in the world. While most have seen a picture of them, many may not realize that beneath the more than 300 iconic heads are bodies, which archaeologists have now excavated. The Easter Island heads are known by the Rapa Nui people as Moai (their ancestors carved them). Researchers have dated them from 1100 to 1500 A.D.

Photo Courtesy: Horacio_Fernandez/Wikipedia

Researchers have long wondered about the location of the statues on the remote and tiny island in the South Pacific. Recent studies of their platforms may shed light on the mystery. What researchers noticed is that the statues are generally located near freshwater sources. Carl Lipo of Binghamton University in New York told The Guardian that the location of the statues near freshwater shows that “they are integrated into the lives of the community” and are not a “weird ritual place.” 

Baghdad Batteries

The National Museum of Iraq holds a small earthenware jar that some believe to be an ancient battery. It’s generally thought that Count Alassandro Volta invented the electric battery in 1800. However, that small jar may mean he was not the first to invent it. While it is unknown whether Konig excavated the jar or found it within the museum, it is believed that it comes from Khujut Rabu, near Baghdad.

Photo Courtesy: Wikimedia Commons

The jar is only five inches tall and contains a copper cylinder with an iron rod inside. Not everyone thinks the jar is an ancient battery — some think it was used as a container for papyrus scrolls. The Parthians lived at Khujut Rabu and were known for fighting, not technological advancements.

The Gedi Ruins of Kenya

Along the coast of Kenya are the ruins of a historic town called Gedi. Swahili people lived in the town, which was primarily constructed from stones and rocks. The town, which dates back to the 15th century and has been designated a historical monument, sits on 108 acres of land.

Photo Courtesy: I, Mgiganteus/Wikipedia

The town was eventually deserted in the 17th century, but why it was deserted remains a mystery. Some theories suggest the city was attacked, either by an army from Mombasa that overran the city while en route to attack Malindi in 1530, or the Galla people around 1600. Another theory is the well dried up and locals abandoned the town due to lack of drinking water

The Cave of Altamira

Ancient Europeans developed cave art across the continent from 3500 to 1100 B.C. A cave in Northern Spain serves as an example of Paleolithic art. Designated a UNESCO World Heritage Site in 1985, the art was first discovered in 1876 by a nobleman named Marcelino Sanz de Sautuola. Three years later, he returned to the cave and excavated the entrance where he found animal bones and stone tools.

Photo Courtesy: Museo de Altamira y D. Rodríguez/Wikipedia

Although prehistorians at the time Sautuola discovered the cave paintings dismissed them as mere forgeries, by the end of the 19th century they were believed to be genuine examples of Paleolithic art. While similar caves have soot deposits, the Altamira caves do not. That seems to suggest the people who painted the cave walls had advanced light technology, creating less soot than the fat lamps and torches typically used at the time.

Hemet Maze Stone

A Southern California rancher surveying his ranch in 1914 discovered a mysterious boulder with a maze design. Although the Hemet Maze Stone has only one carving, it’s a fascinating one. This maze-like design has only been found at a few other sites in North America and all of them are in California.

Photo Courtesy: Devin Sean Cooper/Wikipedia

Archaeologists have no idea about the origin or meaning of the design on the stone. What they do know is that it’s at least 500 years old. There are theories that have mostly been debunked, including the theory that shipwrecked Chinese sailors carved the design. The stone and the land it is on were designated a state landmark in 1956, and because vandals defaced part of the design in the past, a chain-link fence now surrounds it.

The Piri Reis Map

Bay Halil Etham, director general of the Topkapki Palace in Istanbul, Turkey, discovered a mysterious map in 1929 while the palace was being turned into a museum of antiquities. Some researchers think it’s the oldest existing map of the Americas.

Photo Courtesy: International Maritime Organization/Flickr

What confounds people is that the map contains an accurate rendering of Antarctica about 300 years before the continent was discovered. It’s also baffling that the map shows Antarctica not being covered by ice. Experts say the last time Antarctica was ice-free was 6,000 years ago. Did Piri Reis draw the map based on an ancient one he found? It may never be known.

Mysterious Roman Geometrical Devices

Mysterious ancient geometrical devices called dodecahedrons have been found throughout Europe. The devices are 1.5 to four inches, have twelve faces of equal size and each side has a hole in the middle. About a hundred of the devices have been discovered, and through testing, researchers have determined they date back to 100 to 200 A.D.

Photo Courtesy: Wikimedia Commons

No one knows exactly what the devices are or their purpose, despite the number of them that have been discovered. All researchers know for sure is that they’ve been found in areas where the ancient Romans lived. Some researchers believe the devices were candle holders that may have been used in religious rituals. Others think the sides represent the 12 Zodiac signs. 

Hagar Qim

On the island of Malta, there’s an ancient temple complex dating back to the Neolithic era (around 3600 to 3200 B.C.). The temple, called Hagar Qim, which means “worshipping stones,” is one of the main Neolithic temples on the island, but is not the only one. First excavated in 1839, the temple complex has a central building and the remains of a few other structures.

Photo Courtesy: Hamelin de Guettelet/Wikipedia

Hagar Qim is different from other Neolithic temple complexes as it has only one temple where the others have two or three. Designated a UNESCO World Heritage Site, researchers are not certain who built Hagar Qim, but think people migrating from Sicily are responsible for its construction. 


In 1923, a member of a research team in Inner Mongolia found an animal skull. Roy Chapman Andrews, the man who led the team, described it as “the superb skull of a gigantic beast.” The skull is almost three feet long with large teeth. Eventually, the skull was named Andrewsarchus mongoliensis, in honor of Andrews.

Photo Courtesy: Ryan Somma/Wikipedia

Andrews and his team were baffled by the skull, and he deduced that it belonged to an ancient carnivore, but the rest of the team disagreed. One member of the team thought it belonged to an extinct type of omnivorous pig, while another drew the skull and sent it to a museum. Researchers believe the skull belongs to a species that lived around 45 million years ago, but they still do not know the exact species.

What they do know? Based on the size of the skull, the animal was six feet tall at the shoulder and 12 feet long.

Eskimo Belt Buckle

A University of Colorado team discovered what appeared to be a belt buckle while excavating a 1,000-year-old Inupiat Eskimo settlement in Cape Espenberg, Alaska in 2011. The place where the team found the artifact is within the Bering Land Bridge National Preserve. For this reason, the University of Colorado team characterizes the mask as the “first prehistoric bronze artifact made from a cast ever found in Alaska.”

Photo courtesy: University of Colorado Boulder

The artifact consists of a rectangular bar that is connected to a broken circular ring. It is roughly two inches by one inch and less than one inch thick. Researchers tested a small piece of leather wrapped around the rectangular bar, which produced a radiocarbon date of around 600 A.D.

“I was totally astonished,” said University of Colorado-Boulder research associate John Hoffecker. “The object appears to be older than the house we were excavating by at least a few hundred years.”