Evolution of Alfisols in northwestern Turkey in genetically isolated pockets on concave landforms is a unique phenomenon. The objective was to investigate the properties and genesis of these Alfisols. These soils are developed on limestone parent materials of Tertiary age and are found alongside Inceptisols in the karstic landforms. The soils are largely a product of microtopographic differences, which modify distribution of water across the landscape. These soils are deep, show A-Bt-C horizons which are chromic and have strong argillic B horizons. Textures of surface horizons arc clay to clay loam, and subsurface textures are clay. The soils are slightly acidic to slightly alkaline. The minerals identified are chlorite and illite and are the major minerals followed by a lesser amount of chlorite-smectite. Quartz and plagioclase feldspar are present in trace amounts in all horizons, The soils are allocated to the class of Typic Rhodoxeralfs. The concavity of land surface and Mediterranean type of climate facilitate argillic horizon development.