A ruined old blacksmith forge built...

A ruined old blacksmith forge built inside a natural cave, 30x30 blocks. Weathered stone brick and cobblestone walls, cracked and mossy, with an old anvil, rusted iron tools, a broken furnace, and a cold forge pit. Stalactites hanging from the cave ceiling, dim torches, some rubble on the ground. Abandoned and overgrown feel, dark cave stone blending into the ruins.