Some 1,900 years of history are embodied in this castle located in the heart of the city. The Romans first built a forum on this site, and you can see the remains of massive 3m-thick (10-ft.) stone walls. The Normans constructed a castle on what was left of the Roman fort, and much of the Norman work still exists, added to by medieval lords. It came under assault in the Anglo-Welsh wars and was besieged during the English Civil War. The third marquis of Bute, by then the owner, had it restored in the 19th century by Victorian architect William Burges, who transformed the interior into the extravaganza of whimsy, color, and rich architectural detail you see today. The Welsh Regimental Museum and the First Queen's Dragoon Guards Regimental Museum are also here. Admission includes the full conducted tour.