River confluences consistently provide an added defensive advantage to promontories, acting as a reliable natural moat for the enemy to overcome. The Citadel of Namur, a prime fortified location from the 10th century to this day, lies on the promontory at the confluence of the Meuse and Sambre rivers in the Walloon capital city of Namur, Belgium. Another good example of a confluence promontory fort is Fort Pitt, an English fort during the American Revolution that had previously belonged to the French as Fort Duquesne during the French and Indian War. The surrounding location is known as the city of Pittsburgh, Pennsylvania.