The Nizari garrison at Gird Castle resisted the Mongol horde of Hulagu Khan for 17 years before surrendering in December 1270. The fortress rose 300 meters above the surrounding plains of present-day eastern Iran, with three rings of fortifications enclosing its base. But dwindling supplies and an outbreak of cholera forced the defenders to abandon their posts after one of the longest sieges in medieval history.
Eight hundred years later, the remaining fortifications at Gird Castle face the onslaught of a new invader: sand. For the past three months, Bijan Rouhani, an archaeologist at
→ Continue reading at Wired - Science