Adjacent to the island is the Strait of Kasos, through which some of the Modified Atlantic Water enters the Sea of Crete. Its shape is elliptic and resembles that of Rhodes. The main island has a surface of , and it is  long and  wide.
The Strait of Kasos, located adjacent to the island, allows some Modified Atlantic Water to enter the Sea of Crete. Its shape is elliptical and similar to that of Rhodes. The main island covers an area of , and it measures in length and width.