Immediately north of Tatvan, the extinct volcano of Nemrut Dağı – no relation to the mountain with the statues – rises to 3050m. Six thousand years ago Nemrut is believed to have stood 4450m tall; as a result of a huge volcanic explosion, the whole upper section of the peak was deposited in the Van basin, thus blocking the natural outlet and creating the lake. The present-day volcanic cone, which is accessible after snowmelt from May or June through to November, contains two crater lakes, one of which is pleasantly warm.

From the rim, an asphalt road drops down and right towards the crater floor. To reach crescent-shaped Soğukgöl (cold lake), bear left on a dirt track. The lake occupies the western half of the crater, and on its east shore there are some swimmable hot springs. Better for a dip, however, is smaller Sıcakgöl (warm lake), connected to its partner by a narrow path leading east or a left branch off the asphalt road and heated to 60°C by ongoing volcanic activity. The 7km-diameter crater is lushly vegetated (beech, aspen and juniper), contrasting sharply with the bare landscape outside. In summer Kurds graze their flocks on the slopes.

A small ski resort on the mountain, 8km from Tatvan at an altitude of 2200m, holds a smart new hotel, the Nemrut Kardelen. A chairlift ride takes visitors to the summit for TL10, but only runs in summer for groups of ten or more. The lift goes right to the crater rim, and the views are spectacular.