Nemrut (volcano) of the earliest trade routes. Two eruptions of Nemrut were probably witnessed by people of Urartu, an ancient state located in the eastern Turkey. These eruptions occurred c. 787 BC (period of King Menua) and c. 657 BC (period of King Rusa II), and the latter eruption might cause the sudden disappearance of the city Uaiais located 30 km east of Süphan. In the 1980s, Japanese volcanologists studied the evolution of gases inside the caldera of Nemrut. They found that the ratio of helium isotopes He/He is 1.06, which indicates volcanic activity (most of the measured helium evolved from the
Mount Nemrut on this monument. The eastern portion is well preserved, being composed of several layers of rock, and a path following the base of the mountain is evidence of a walled passageway linking the eastern and western terraces. Possible uses for this site are thought to have included religious ceremonies, owing to the astronomical and religious nature of the monument. The arrangement of such statues is known by the term hierothesion. Similar arrangements have been found at Arsameia on Nymphaios at the hierothesion of the father of Antiochus, Mithridates I Callinicus. When the Seleucid Empire was defeated by the Romans in