Mount Parnitha just north of Athens has over 20 caves and chasms, the most known being Pan’s cave which was a place of worship dedicated to the god Pan in antiquity. Mount Hymettus (Imittos) is composed of slate on lower ground and limestone on higher ground which can store water, yielding many springs like at the Kesariani Monastery, Asteriou Monastery, Agios Ioannis Theologos Monastery, Kareas and Kalopoula. The limestone topography has given rise to over 60 caves in the area. Most have been explored but it is expected that there are still many other unexplored ones.