Current results of an arachnological survey of some sandstone rock sites in Bohemia (so called 'rock cities'). The spider fauna of the Adrspach·Tepllce rocks was investigated. Some records on spider fauna of other nine sandstone rock areas are included. The phenomenon of 'rock cities' manifests itself in three aspects: (1) In the bottom parts are microclimatically cold spaces, frequently hosting northern or mountain species of invertebrates, which here have an azonal occurrence. (2) The sun exposed tops of rocks can host thermophilous species. (3) Some species are limited to the surface of rocks and boulders. These are referred to as lithophilous or lithobiont species
