Kamalamai is a municipality in Sindhuli District, in the Janakpur zone of central south Nepal. At the time of the 2011 Nepal census it had a population of 39,413 people in 9,304 households. The city is located in the Sindhuli Valley of central south Nepal. The historic symbol of the valley, Sindhuli Gadhi fort, is at the peak of a hill of the Mahabharata range. The city is in the plain valley made by the Kamla River. Kamalamai Municipality is the largest municipality of Nepal according to area.