While the Lost City of Atlantis may never be found - or perhaps more likely, never existed in the first place, there are other lost submerged cities. Ancient Egypt's Lost City of Heracleion (also called Thonis) is perhaps the greatest submerged city ever discovered and we are only just starting to learn more about it.

Excavations are continuing and every year there are more and more discoveries being made of this ancient city that had been lost under the waves for over a thousand years. Before it was barely more than a legend that only appeared in a few rare ancient texts that most historians didn't bother much with.


The Once Great Port City of Heracleion/Thonis

"Appearing in a few rare inscriptions and ancient texts, the city of Thonis-Heracleion was hidden away for thousands of years, submerged deep under the sea."

Atlas Obscura

Of course, the city wasn't originally built underwater. In ancient times it was built on some adjoining islands in the Nile Delta. There were a number of harbors and was interested by canals. Its wharves, temples, and tower-houses were linked by ferries, bridges, and pontoons. It was one of the trading ports of Ancient Egypt - and even the main trading port by the Late Period of Egypt.

  • Port: At One Time It Was The Main Port City Of Egypt
  • Age: Perhaps As Old As The 12th Century BC

The city was the stuff of legends and few ever thought it really existed. The legendary beginnings of Heracleion (or Thonis) go back as far as the 12th century BC.

It was mentioned by some of the ancient Greek historians including Herodotus, Strabo, and Diodorus. Herodotus even claims that the city was visited by Paris and Helen of Troy before the outbreak of the Trojan war (they sought refuge there but were turned away by the city). The site of Troy has been discovered and excavated in Turkey and one can visit today.

  • Mentioned: By Herodotus, Strabo, and Diodorus

The city was also home to temples, including the large temple of Khonsou the son of Amun (although later on, the worship of Amun become more important). There was also the significant temple of Amun-Gereb in the middle of the city.

  • Heyday: Between the 6th and 4th Centuries BC

Over time the newly founded city of Alexandria superseded Thonis as the main Egyptian port in the second century BC.

Related: Sunken Treasure: Battle For San Jose's "Holy Grail Of Shipwrecks"

Heraclaion/Thonis Lost Beneath The Waves

Over time the central island on with the city succumbed to soil liquefaction. It had been weakened by a combination of earthquakes, tsunamis, and rising sea levels. What had been hard clay, become liquid and the building built on it collapsed into the water.

  • Succumbed: To Soil Liquefaction
  • Date Sank: Sank From The End of 2nd Century BC To The 8th Century AD

This didn't happen overnight by likely started at the end of the 2nd century BC with only a few residents still calling it home by Roman times. By the time of the arrival of the Arabs at the end of the 8th century AD, it had completely disappeared beneath the waves.

This inundated ancient city now rests 2.5 kilometers ro 1.6 miles off the coast and under 30 feet or 9.1 meters of water. It is an easy 32 km or 20 miles from the large Egyptian city of Alexandria.

  • Distance: 2.5 km or 1.6 miles Off The Coast
  • Depth: 30 feet or 9.1 Meters Of Water

Related: The Lighthouse Of Alexandria And What Can Be Seen Today

Discovery & Excavation

The ruins of the city were first discovered in 1933 as Royal Air Force commander saw the ruins while flying over the bay. That that time most historians thought that Thonis and Heracleion were different cities on the Egyptian mainland.

  • Spotted: In 1933 By The Royal Air Force
  • First Excavation: In 1999

Exploration of the ruins began in 1999 by the French archeologist Franck Goddio. Numerous finds from the city's ancient history were uncovered - including that of statues of the god Serapis and the queen Arsione II.

  • Fun Fact: Queen Arisone II Became the Ptolemaic "King of Upper and Lower Egypt"

A stele recovered from the site shows that it was known by both its Greek and Egyptian names. Heracleion was an ancient Egyptian port city located near the Canopic Mouth of the Nile River on the Mediterranean Sea.

In the last couple of years more temples, wicker baskets with palm tree fruits, statuettes of the god Osiris, wooden sofas, gold amulets, a Ptolemaic galley ship, and other finds have been discovered and excavations of the underwater site are continuing today.

There remains most of the city to be explored, in 2010 a type of ancient Nile riverboat was discovered, in 2019 a small Greek temple was found along with treasure ships and bronze coins from the reign of Ptolemy II.

Next: Lost City Of Atlantis: 25 Things We Thought Were True (But Are Actually False)