Paleokarst surfaces developed in gypsum deposits are present in two distinct situations within the Miocene evaporite formations of the Madrid Basin: 1) paleokarst surfaces related to major sedimentary breaks and 2) incipient paleokarsts at the tops of the evaporite sedimentary sequences (sedimentary diastems). The karstification features are varied and include small dolines, networks of chimneys and fissures as well as collapse frameworks. Emphasis is placed on the role of bush vegetation in promoting dissolutional features of the gypsum karst, which is clearly evidenced within the sedimentary diastems