Ramsar is a city in and the capital of Ramsar County, Mazandaran Province, Iran. At the 2012 census, its population was 33,018, in 9,421 families. Ramsar lies on the coast of the Caspian Sea. It was also known as Sakhtsar in the past. Natives of Ramsar speak the Gilaki language which is a member of Northwest-Iranian languages and a dialect of Persian along with Mazandarani. The town is known for having some of the highest levels of natural background radiation on Earth.