Climate, earthquakes, materials, and topography had been the primary design parameters, and were respected with admirable honesty & ingenuity. A special ergonomic scale is all too obvious, very similar to the one found in ships: low doors, narrow and steep stairs, tiny inner/outer spaces.

These are products of necessity rather than choice, since the dominant design rule is economy in every respect. Certain additional features differentiate the architecture of Santorini from that of the surrounding islands: excavated buildings in a stepped-back layout and cylindrical vaults.

The slope & hardness of the ground, coupled with the need for material saving, led to the creation of vaulted caves (gr: iposkafa). The deep caves are usually divided in a row of 2-3 rooms with partitions imitating the front walls. Typically, the front openings are the only entries of daylight & fresh air in those deep spaces. Besides the ease of construction, a major advantage of the excavated dwellings is their thermal performance, because it is achieved in summer & winter, with a reduced need for auxiliary heating which is required mainly to reduce humidity that causes discomfort.

These cave-like structures are particularly earthquake-proof: During recent restoration works, several excavated rooms were found intact, buried behind ruined facades. The major construction difficulty, even today, has been the transport of building materials over cliffs & steps with the only available -and most appropriate for the terrain- means: donkeys & mules. That difficulty explains odd features such as massive rock chunks left on verandas, or half-ruined walls merged into later structures. The excavated walls of caves are sometimes 'adorned' by protruding rocks, left as they were found during construction in order not to alter the stability of the ground or to increase the transportation burden.