Bobby's Panic Room
From Super-wiki
Sam: You built a panic room??
Bobby: I had a weekend off.
In 4.02 Are You There, God? It's Me, Dean Winchester, while being attacked by the Witnesses, Bobby leads Sam and Dean to a safe room in his house. It is a cylindrical room, completed lined in iron coated in salt to keep spirits from entering. In the roof is a large extraction fan, below which is a grill with metal work in the shape of a Devil's Trap.
The room has a bed, and appears well-stocked with supplies and equipment. There is an iconic poster of Bo Derek from the movie 10 on the wall.