A 1.3 km tunnel has been discovered 13 metres beneath the Ptolemaic temple of Taposiris Magna, west of Alexandria.

The massive 2 metre high structure appears to be similar to the Eupalinian Aqueduct on the island of Samos, and is thought to have been used to transport water to the city.
The tunnel was discovered during excavations of the now submerged foundations of the temple.