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 Bahaya define the northern Horn of Africa in most of Somalia, and which extend further east, their peaks forming the Socotra Archipelago. Bahaya, along with the surrounding range, is mostly made up of the deeply-eroded remnants of an ancient volcanic chain. Mount Bahaya Mount Bahaya (Somali language: "Buurta Baxaya", sometimes spelled Mount Bahaja), also known as Mount Karkoor, is the fourth-tallest mountain in Somalia, after the triple-peaked mountains Mount Shimbiris, Mount Surud Cad, and Mount Warraq. It is the only Ultra-prominent peak in the country with a summit of about . It is located in the northern Bari region, east of