The traditional architecture of Santorini is similar to that of the other Cyclades, with low-lying cubical houses, made of local stone and whitewashed or limewashed with various volcanic ashes used as colours. The unique characteristic is the common utilisation of the hypóskapha: extensions of houses dug sideways or downwards into the surrounding pumice. These rooms are prized because of the high insulation provided by the air-filled pumice, and are used as living quarters of unique coolness in the summer and warmth in the winter. These are premium storage space for produce, especially for wine cellaring: the Kánava wineries of Santorini.
The island is the result of repeated sequences of shield volcano construction followed by caldera collapse. The inner coast around the caldera is a sheer precipice of more than 300 m drop at its highest, and exhibits the various layers of solidified lava on top of each other, and the main towns perched on the crest. The ground then slopes outwards and downwards towards the outer perimeter, and the outer beaches are smooth and shallow. Beach sand colour depends on which geologic layer is exposed; there are beaches with sand or pebbles made of solidified lava of various colours: the Red Beach, the Black Beach, the White Beach, etc. The water at the darker coloured beaches is significantly warmer because the lava acts as a heat absorber. Santorini has a group of islands. Those islands are named, Thera, Thirasia, Aspronisi, Palea, and Nea Kameni. They were are created by volcanoes and are located in the Aegean Sea just north of Crete.