The oldest, yet most distinctive house construction type in Santorini is the famous cave houses. That simple form of establishment originally hosted ship crews and later on the less privileged islanders. A cave house is an oblong shaped building with an arched roof, sculpted in the caldera rock or the mainland area. The front part consists of the kitchen and the living room and the back part is where the bedroom is while the bathroom is usually built outside the house. The lighting and ventilation is left exclusively to the front door arch that includes windows to the left and right of the door as well as a round, iron skylight right above them. The natural air-conditioning that the insulation of the pumice the cave houses are built with provides, allows the building to preserve an almost steady temperature thus making it cool during the summer and warm during the winter. Nowadays, cave houses have become popular hosting quarters for visitors and permanent residents as they have been modernized with all of today’s comforts. A lot of them can be found along the caldera, in areas such as Vothonas, Foinikia, Karterados, Pyrgos, Emporio and Akrotiri.