Geologists believe that about ten crore years have passed when Kashmir Valley which was once a lake called Satisar, the lake of goddess Sati, came into its present form.

For hundreds of million years Kashmir Valley remained under Tethya sea and the high sedimentary-rock hills seen in the valley now were once under water. Geologists have come to believe that Kashmir Valley was earlier affected by earthquakes. Once there was such a devastating earthquake that it broke open the mountain wall at Baramulla. and the water of the Satisar lake flowed out leaving behind lacustrine mud on the margins of the mountains known as karewas. Thus came into existence the oval but irregular Valley of Kashmir. The karewas being in fact the remnants of this lake confirm this view. The karewas are found mostly to the west of the river Jhelum where these table-lands attain a height of about 380 meters above the level of the Valley. These karewas protrude towards the east and look like tongue-shaped spurs with deep ravines.

Ancient legends and popular traditions say that Samdimat Nagar, capital of the kingdom of Sundra Sena, was submerged as a result of an earthquake, and the water that filled the area formed the Wular Lake, the largest fresh water lake in India. The oldest igneous rocks are still found at Shankaracharya hill. When the whole Valley of Kashmir was under water this hillock was the first piece of dry land lying in the form of an igneous island.