Catacombs in the Kerch suburb of Adzhimushkay (Аджимушкай) have been a source of construction material for the city from time immemorial. Early Christians held their clandestine services here in the 2nd century AD. When the Germans sacked Kerch in May 1942, 10,000 Soviet troops and civilians (many of them Jewish) descended into the catacombs and held them for 170 days until all of them were gassed or captured. You can relive their experience on a tour of this museum, which takes you through the unlit caverns turned by the defenders into barracks, hospitals, classrooms and cemeteries. The tour is in Russian, but the scenery speaks for itself. Take something warm to wear – it gets very chilly underground. To get here, catch bus 4 for the 'Muzey' stop from the bus station.