The interesting rock formations, known as "fairy chimneys", have been formed as the result of the erosion of this tufa layer, sculpted by wind and flood water, running down on the slopes of the valleys. Water has found its way through the valleys creating cracks and ruptures in the hard rock. The softer, easily erodable material underneath has been gradually swept away receding the slopes and in this way, conical formations protected with basalt caps have been created. The fairy chimneys with caps, mainly found in the vicinity of Urgup, have a conical shaped body and a boulder on top of it. The cone is constructed from tufa and volcanic ash, while the cap is of hard, more resistant rock such as lahar or ignimbrite. Various types of fairy chimneys are found in Cappadocia. Among these are those with caps, cones, mushroom like forms, columns and pointed rocks.