I'm doing some Medieval. This doesn't happen very often so pay attention :)
In York, along one of the popular street of shops, you'll find a little door between two shop which opens to a narrow alley, which takes you to small courtyard and the remains of a 12th century house.
Called the Norman House, it's claimed as the oldest house in York. You can see where a cupboard, a window arch and where the floor was (under the window). The lower section being a basement/cellar.

