Manjarabad Fort is a fort located in the Indian state of Karnataka. It was built in the 18th century by the ruler of Mysore, Hyder Ali. The fort was constructed with the purpose of controlling the route between the coastal city of Mangalore and the interior city of Mysore. The fort is located on a hillock and is surrounded by a moat. The fort has two main gates and several bastions. The fort was captured by the British in 1799 and was used as a prison during the 19th century. The fort was abandoned in the 20th century and is now in a state of ruin.