It has a rocky, indented coastline and is about 53 kilometres long by 10 to 19 kilometres wide. The island is well watered, the principal rivers being the Santon, the Silver Burn, the Neb-Rhenass, the Sulby, near Ramsey, and the Dhoo and Glass rivers, which form the River Douglas.
Mountains extend nearly the length of the island.
Some of the valleys have rich pastures, and livestock is raised extensively. Mean Time summer, Greenwich Mean Time plus 1 hour winter.