This morning we set out for a thrilling tour to Askja Volcano in Super Jeeps (12-13 hours; $367/person). These large 4x4 vehicles have been modified with big tires and extra shock absorption to provide a more comfortable ride over offroad terrain, allowing us to penetrate deep into Iceland’s central highlands. First, we hiked in Drekagil (Dragon) Canyon, then explored the massive Askja Caldera, formed when the volcano erupted in 1875. Lake Askja, which fills part of the caldera, is one of the deepest lakes in Iceland at nearly 700 feet. The caldera contains several overlapping craters with active volcanoes beneath, including Viti, which warms a sulphuric blue-green crater lake—the more adventurous among our ranks may even opt for a dip in the tepid water!