There are many underground settlings opened in historical times in Cappadocia region and the Gumusler Monastery is one of these. The monastery is a rock monastery church located in approximately 8 km northeast of Nigde. The most important characteristics of the monastery dated in 11th century ac are that it is an important settlement and touristic area that contains the most preserved frescoes in Cappadocia region. For this purpose, were determined the geological features of the observed units in the areas where the monastery is located and the surroundings were determined. Engineering geological problems are mentioned for the negative effects of the discontinuities especially in the monastery part. During field studies, stones with different color and textural characteristics were taken into account and sampling was carried out from four different levels. On representative samples, laboratory studies were conducted for determining the mineralogical, chemical, and petrographic and geomechanical properties. Underground cavities in the region were opened in the lower part of the KA +/- zA +/- lkaya ignimbrite which has relatively more rock fragments. Higher amount of rock fragments in the lower part makes this level easier to cave in. Low welding rate of the rock is believed to be the cause of having relatively low values of engineering properties of the lower levels of examined ignimbrites. Ignimbrites in these levels are more sensitive against atmospheric conditions than those in the upper levels. This study is the first study to determine engineering geology problems in the GumuAYler archeological area and provide data to planned conservation measures.