The Castle Keep in Castlevania (Nintendo 64) and Castlevania: Legacy of Darkness is like other Castle Keeps that have appeared in Castlevania games, except that it has several rooms chained together. A series of bosses must be fought, depending on actions taken in the game and the characters played with.
Notice the ledge that wraps around Dracula's keep. The flames blocking the ledge are illusionary (scenery?) and harmless, traversing the ledge around Dracula's keep leads to the last torches in the game behind the keep. Nothing remarkable, but every bit helps if you're in need of it. A invisible path to a floating torch is also back there, take care not to fall.