Kaludiya pokuna, Black water pond is the largest among the man-made ponds in Mihintale ancient hermitage complex. This magnificent pond is situated at the foot of the western slopes of Mihintale and is shaded by humungous trees and surrounded by ruins. One and a half kilometers to the south-west of Mihintale and at the foot of mount Anaikutti lies the pond.
This man made pond is 200 feet long and 70 feet wide. The somber reflections of trees and boulders of the neighbouring mountains make to visualize the water in the pool as in black colour at most times of the day. Therefore it is called by the name Kaludiya pokuna. It is believed that this pond was used as a place to observe Pohoya Karma ( cardinal tenets). Around the pool are the ruins of meditation halls, bathing houses and walled caves. The well planned building complex around the pond is a witness to an advanced hydraulic culture with artificial moats running through a few houses in ancient Sri Lanka.