The Siege of Farnham Castle (July 1642) was a siege action of the First English Civil War. Farnham Castle, located in Surrey, was a Royalist stronghold at the start of the war, and its small area of control was entirely surrounded by Hampshire. It was an important bastion of Royalist power in southern England, and the Parliamentarian general Oliver Cromwell reduced the castle after an assault.
The Parliamentarians brought up their saker cannons, pounding at the walls and reinforced gates relentlessly. The small garrison of Farnham was disheartened by the bombardment, and they were routed shortly after the Parliamentarians breached the castle. The capture of Farnham deprived the Royalists of another one of their footholds in southern England.