Charles Fort is a classic example of a late 17th-century star-shaped fort and is was one of the largest British military installations to be built in the country. It is named after King Charles II of England and was designed by the famous architect Sir William Robinson to specifically resist canon attack (Robinson also designed The Royal Hospital in Kilmainham0, St Michan’s Church and parts of Dublin Castle. On the opposite bank are the impressive ruins of James Fort which was built 80 years earlier in 1602 and named after King James I. Both forts have been associated with some of the most momentous events in Irish history and saw action when both forts were attacked by the Williamite forces after the Battle of the Boyne and also during the Irish Civil War of 1922-23. Charles Fort was used by the British as a garrison right up to 1922. It was declared a National Monument in 1973 and is now under state care and is now open to the public for a small fee.