Mazandaran Province is a Caspian province in the north of Iran. Located on the southern coast of the Caspian Sea. Sari is the largest and the capital city of Mazandaran province. Mazandaran is one of the most densely populated provinces in Iran and has diverse natural resources, especially large reservoirs of oil and natural gas. The province's four largest counties are Sari,Behshahr,Babol, and Amol. The diverse nature of the province features plains, prairies, forests and rain forest stretching from the sandy beaches of the Caspian Sea to the rugged and snow capped Alborz sierra.