It was used as a fortress right up until the end of the English Civil War, during which it was a Royalist headquarters. When Parlementarian forces finally captured it, they razed it so it could never be used again.
fact 1) during the long siege under a bombardment, a musket ball smashed through the grand hall window and grazed the earl of worcester on the forehead. when asked if he was hurt he replied 'i was told i was head strong as a child, and i'm still headstrong as an old man now my head has been make musket proof. true cavalier wit!
fact 2) the siege lasted so long that the roundhead commanders brought a large mortar cannon called 'mons meg' to haul large grenades into the castle to cause huge damage!
hmh, why do i have the Feeling that ill be in Wikipedia in 3, 2, 1, .. yes i am. ^^
Imagine seeing a freshly constructed castle, before the weather has time to work on it.