Catacombs are underground labyrinths created during the period of the city construction over 200 years ago. They are situated mainly in Nerubaiskoe village (15 km from Odessa), originally created during mining of hardware materials as shell rock that were used to build the city. Currently it is the labyrinth with hundreds of entrances, exits, caves, and tunnels. Before the WWII labyrinths were the place for smugglers. During the WWII this place was used as a shelter for the partisans.