In the basement Museum Tre Kronor, you can see the foundations of 13th-century defensive walls and items rescued from the medieval castle during the 1697 fire. The museum also describes how the fire started (a fire watcher was off flirting with a kitchen maid, it seems) and explains rather vividly the meaning of 'run the gauntlet' (which in 1697 was how the court punished watchmen for flirting with kitchen maids while fire destroys a castle).
