Secret behind a locked door

The B&B we are staying in has three rooms. We are in one called "Hayloft", so named because it used to be .... a Hayloft. Below it were the carriages and horses. The whole building was originally outbuildings and accommodation associated with a small Manor House some way up the hill.

Our bathroom has a locked wooden door on one wall. We could easily stay here and have no idea what lies on the other side - a secret of sorts. But we have established that this is where the pottery is located - a showroom upstairs (on the other side of the door) and the pottery itself downstairs.