On the way to the top, at an altitude of some 630 meters, at the northwestern mountainside, you will find the biggest cave of the island, the Cave of Zas. According to the local myths, it is here that the king of Olympus lived during his childhood. Archaeological finds indicate that in antiquity the cave was dedicated to Zeus who was worshipped here, whereas during the prehistoric times it was used as a place of abode.
The cave presents speleological interest too. The interior has an excellent decoration and the visitor will see fascinating and impressive formations of stalactites and stalagmites.
Just by the entrance of the cave it is situated the small church dedicated to Zoodochos Peghe (“Virgin, Spring of Life”). The church had been established during the Ottoman domination, when the cave served as a shelter of the Christian population of the area.
Access to the cave is easy enough, following the old, well preserved footpath departing from the spring of Aria and continuing up to the top of the mountain.