The site was excavated by the British Museum, 1878-1881 by Patrick Henderson, 1911 by D. G. Hogarth and R. C. Thompson, and from 1912 to 1914 by C. L. Woolley, and T. E. Lawrence ("Lawrence of Arabia"). Excavations were interrupted in 1914 by World War I, resumed in 1920 with Woolley and then ended with the Turkish War of Independence. These expeditions uncovered substantial remains of the Neo-Hittite and Neo-Assyrian periods, including defensive structures, temples, palaces, and numerous basalt statues and reliefs with Luwian hieroglyphic inscriptions.