Archaeologists have discovered a huge, impressive tunnel beneath a temple in the ancient ruined city of Taposiris Magna on the Egyptian coast, which experts are calling a “wonder of geometry.” During ongoing excavations and studies of the temple, Kathleen Martinez and her colleagues from the University of Santo Domingo in the Dominican Republic discovered the structure 13 meters (43 feet) underground. The 2 meter high tunnel was cut through an incredible 1,305 meters (4,281 ft) of sandstone.

According to the Egyptian Ministry of Tourism and Antiquities, its design dates back to B.C. on the Greek island of Samos. It is quite similar to the 1,036-meter Eupalinos Tunnel, a 6th-century aqueduct. Often called an engineering marvel, the design and construction of the pipeline was unique.

Although the Taposiris Magna Tunnel is unique, its engineering is still equally impressive. Parts of the Taposiris Magna Tunnel are flooded, but its purpose is currently unknown, other than its similarity to the Eupalinos Tunnel.

Martinez, who has been working to search for the lost tomb of Cleopatra VII in Taposiris Magna since 2004, believes the tunnel may hold promise. Previous excavations had uncovered clues pointing to the famous queen and the last of the Ptolemies.

Taposiris Magna was founded around 280 BC. By Ptolemy II, son of the famous general Alexander the Great and one of Cleopatra’s ancestors (reigned from 51 BC until his suicide in 30 BC). The team believes that the temple was dedicated to the god Osiris and his queen, the goddess Isis, with whom Cleopatra had a strong relationship. Coins with the names and images of Cleopatra and Alexander the Great, as well as figures of Isis, were also found here.

Tomb walls containing Greco-Roman tombs were also found in the temple. If they were found there, it is possible that Cleopatra and her husband Mark Antony were buried in such tombs. Future studies may provide more information about whether the new tunnel can lead to these long-lost tombs.

The next stage will be the study of the nearby Mediterranean. A series of earthquakes struck the shore between AD 320 and 1303, causing part of the temple to collapse and be swallowed by the waves. In addition, previous excavations revealed a tunnel network extending from Lake Mariut to the Mediterranean.

Whether or not the tombs are found, in-depth excavation of these ruins can tell us more about the mysterious ancient city. Some treasures have already been found in the tunnel: pottery shards and a rectangular block of limestone. As then Minister of Antiquities Zahi Hawass said in 2009: “If we discover the tomb of Cleopatra and Mark Antony, it will be the most important discovery of the 21st century. “If we cannot find the tomb of Cleopatra and Mark Antony, we will have made great discoveries here, inside and outside the temple.”