The oldest walls found in existence so far are those of the temple of Gobekli Tepe in Urfa, southeast Turkey which date to 11,500 years ago. City walls, which became common for purposes of defense, are first seen around the city of Jericho (now in the West Bank) around the 10th century BCE and the Sumerian city of Uruk which was founded somewhat later (though both cities lay claim to the honor of `first city in the world'). The walls of Uruk were thought to have been built by the great king Gilgamesh upon which he inscribed his heroic deeds which formed the basis for the later epic he is most famous for.