Description Qasr Al Hosn is the oldest and most significant building in Abu Dhabi , holding the city’s first permanent structure; the watchtower. Built around the 1790’s, the commanding structure overlooked the costal trade routes and protected the growing settlement established on the island. Qasr Al Hosn comprises of two major iconic buildings: the Inner Fort (originally constructed in 1795) and the Outer Palace (1939-45). Over the centuries, it has been home to the ruling family, the seat of government, a consultative council and a national archive; it now stands as the nation’s living memorial and the narrator of Abu Dhabi’s history.