This type of dungeon is still in use. Creatures (usually intelligent) live there, although they might not be the dungeon’s creators. An occupied structure might be a home, a fortress, a temple, an active mine, a prison, or a headquarters. This type of dungeon is less likely to have traps or wandering beasts, and more likely to have organized guards both on watch and on patrol. Traps or wandering beasts that might be encountered are usually under the control of the occupants. Occupied structures have furnishings to suit the inhabitants, as well as decorations, supplies, and the ability for occupants to move around. The inhabitants might have a communication system, and they almost certainly control an exit to the outside.
Some dungeons are partially occupied and partially empty or in ruins. In such cases, the occupants are typically not the original builders, but instead a group of intelligent creatures that have set up their base, lair, or fortification within an abandoned dungeon.