Ismer is a sea, that covers 28 000 km². The sea belongs to Ardenjost, Ferribre and Dereb. It has no international waters. Its surrounding provinces are Rjebok, Mostjez, Ismer, Safnar (Ardenjost), Vambasla, Saigara (Ferribre) and Gaptal (Dereb). The depth at the deepest point is approximately 300 metres. Salinity: 2.6% The sea has a big island, Reganesuara, which is in the territory of Ferribre.