From National Geographic: Alexander the Great Conquered City via Sunken Sandbar.

Changing sea levels and shifting sands helped Alexander the Great conquer the ancient island city of Tyre in one of his most famous military victories, new research shows.

In 332 B.C. the Greek military commander invaded the island just off the coast of modern-day Lebanon, then part of ancient Phoenicia.

New geological findings and computer models show that the growth of agriculture on the island caused sediment runoff, which spurred the formation of a long, thin submerged sandbar between Tyre and the mainland.

Alexander and his men cunningly exploited this sandbar, the findings suggest, to build a 0.6-mile (1-kilometer) raised path, or causeway, out of wood and stone. [continue]