Lavasan (Persian: لواسان, also Romanized as Lavāsān) is an affluent town in Shemiranat County, Tehran Province, Iran. At the 2011 census, its population was 28,558, in 7,645 families. The Jajrood River flows through Lavasan. Situated 11 kilometers northeast of Tehran, Lavasan is known for its excellent weather and the luxurious mansions.