The origin of the Çiftlik plain has long been subject to discussion. Pasquarè et al. (1988)'s proposal to identify it with one of the Cappadocian neogene calderas, has been rejected by Le Pennec et al. (1994) and Froger et al. (1998), who locate two neogene calderas in a) the Acıgöl-Nevşehir area, and b) the Derinkuyu plain area. However, Froger et al. (1998) include the Çiftlik plain in their "Derinkuyu caldera". In addition, the Çiftlik plain is usually considered as filled by the sediments of a former lake, the flat bottom of which would correspond to the plain surface more or less modified by the Melendiz river sedimentation and erosion. However, until the present study, no lake sediment had been evidenced in the plain. In this context, three series of questions are presented, and answers proposed about: (i) What is the origin of the Çiftlik plain? i.e. what is the geomorphological definition and designation of the plain according to its genesis and history? Is it:  (a) volcanic or volcano-tectonic, ie a caldera or a remnant of a caldera?  (b) unconnected with any structural bordering, ie an area kept out of the expansion of various volcanic complexes?  (c) a tectonic basin, eg a subsiding basin? (ii) What is the nature and age of its fill? ie to what deposit(s) correspond the plain fill and its surface sediments? ie was the plain ever filled by a lake? what event caused the lake to occur? a dam in a palaeovalley, such as a lava flow, an avalanche, an ash-and-block flow, a mud-or debris-flow? (iii) What are the Early Holocene environmental dynamics of the plain, related to the human occupation in the area as studied in the archaeological excavation of Tepecik-Çiftlik?