Thonis-Heracleion, an ancient Egyptian trading hub, was lost to the sea after a natural disaster and rediscovered in the early 2000s, revealing treasures like large statues, animal sarcophagi, and 2,400-year-old fruit baskets.
Mysterious giant stone jars in northern Laos, believed to have been used as funerary urns and dating back to at least 1240 B.C., remain largely enigmatic due to their unknown purpose and the danger posed by unexploded munitions in the area.
The discovery of twin-handled Roman vases, known as amphoras, in Brazil’s Guanabara Bay by shipwreck explorer Robert Marx in 1982 suggested a Roman presence in Brazil pre-dating the Portuguese by over 1,000 years, but the theory remains highly unproven due to lack of further exploration and accusations of looting.
The Nazca Lines in Peru, a series of enormous geoglyphs etched into the coastal plain over 2,000 years ago, remain a mystery despite over 1,000 designs being located, including animals and plants, and 168 new geoglyphs being discovered as recently as 2022, with their purpose still unknown.
The Paracas Candelabra, a 600-foot geoglyph overlooking Peru's Pisco Bay, dates back to around 200 B.C. and its purpose remains unknown, with theories ranging from navigational tool to representation of a deity's trident.
The Sacsayhuamán fortress, constructed by the Incas in the 1400s, features enormous rocks weighing over 125 tons fitted together without mortar using only bronze and stone tools.
The location of Cleopatra VII and Mark Antony's tomb remains a mystery, with some theories pointing to Alexandria and others to the Nile Delta, along with other legendary lost burial sites such as those of Alexander the Great and Genghis Khan.
The Voynich manuscript, acquired by Wilfrid Voynich in 1912, is a medieval manuscript written in an extinct language or code and filled with strange illustrations, which has puzzled scholars for over a century and remains unsolved.
The Yonaguni Monument, an underwater rock structure off the coast of Japan’s Yonaguni Island, is believed by some to be the ruins of an ancient civilization, while others contend that it is a natural formation.
Stonehenge's function as a burial site is well-known, but many other aspects of its purpose, including its religious, ceremonial, astronomical, and therapeutic significance, remain a mystery.