Farah Citadel

A massive fortress on the edge of Farah City, Afghanistan, with walls reaching 15 meters high and a perimeter extending one kilometer. Known as the Citadel of Alexander, its origins are debated -- some attribute it to Alexander the Great who renamed the city Prophthasia ('Anticipation') in 330 BC after uncovering a conspiracy, while others link it to Zoroastrian warriors under Darius the Great. Artifacts spanning 2,500 years of continuous occupation have been found. The citadel served as a Silk Road way-station between Persia and India, and in the 1980s was used as a Mujahideen arms depot.