Dungeon Gate is one of the surviving pieces of Bursa's old fortified city, near the Tophane side of the historic centre. The restored walls and gate help make sense of the hilltop quarter, where tombs, viewpoints, and Ottoman-era streets sit within an older defensive frame.
See it as part of a walk rather than a standalone attraction. The reward is the way the gate connects Bursa's early urban shape with the imperial monuments nearby, especially if you are already climbing toward Tophane.