Warren House­, with its tasteful Big Bird-yellow exterior, features a curious musty smell that suits the home of the Celtic Studies and Folklore and Mythology departments. It also boasts a period bathroom, complete with its own pull-chain toilet.

But the house’s real piece of history is its trapdoor, which leads to a small compartment big enough for a few escaped slaves to hide. Though the door is hidden under a bench today, the worn notch used to pry open the hinged section of floor still works.

Warren House is unknown to all but a small handful of Harvard students who’ve endeavored to do something crazy like learn a Celtic language (see the Welsh dictionary against the back wall: Volume III is M through Rhywyr). But that doesn’t mean the circa 1833 piece of architecture must remain obscure. Stroll right in, as FM did—just don’t try to use the antique toilet.