Alexander the Great destroyed Tyre with the help of a natural sand-bridge

Geological studies of Tyre have revealed that Alexander the Greats defeat of the island in 332 B.C. was facilitated by a natural sand bridge lying a metre or two below the waters surface.

Washington, May 15 : Geological studies of Tyre have revealed that Alexander the Great's defeat of the island in 332 B.C. was facilitated by a natural sand bridge lying a metre or two below the water's surface.

According to U.S. Military Academy's Department of History, Alexander the Great built this causeway on a natural sand bar at the age of 23

He is said to have stood on the coast of what is now Lebanon, gazing at the tiny Phoenician island city of Tyre, then a powerful commercial centre.

Alexander knew that Tyre had to be seized before he could safely move south to Egypt and then turn inland to conquer the Persian Empire.

His engineers used timber and ruins from the old centre of Tyre on the coast to build a kilometre-long 'mole', or causeway, to the island. Months later, his army broke through the fortress walls and brutally crushed Tyre.

Nick Marriner of the European Centre for Research and Teaching on the Geosciences and the Environment (CEREGE) in Aix-en-Provence, France, says previous historians and archaeologists had no idea of the depth of water between Tyre and the mainland.

Marriner says he and his PhD supervisor Christophe Morhange went to Tyre in 2002 along with a team of geological engineers and drilled over 20 cores on the now urbanized isthmus that today connects the mainland with the former island of Tyre, as well as other scattered nearby locations.

The cores contained sediments from as far back as 8,000 years ago. Lebanese archaeologists did diving surveys.

Back in the lab, the team performed analyses of the types of sediment and tiny fossils within the cores, to learn more about the ancient near-shore marine environment; fine-grained sediments and the remains of creatures that prefer to live in sheltered environments show up when and where waters were once calm. Wave modelling and previous studies of the area helped to complete the picture.

According to them, an elongated region of sandstone reefs acted as a six-kilometre-long natural breakwater in the area 8,000 years ago. This, combined with an increase of sediment supply due to agricultural activity and a rise in inland rainfall, particularly after about 3,000 years ago, created a natural sandbar that sat an average of one to two metres below mean sea level in Alexander's time.

The report appears in Proceedings of the National Academy of Sciences1.

Marriner's work highlights how the natural causeway started to grow faster sometime before Alexander arrived, and accelerated again after Alexander's construction blocked sediment transport in the area.

Marriner says the study should help archaeologists to pick sites in the area for further investigation.

ANI