Wikipedia
Box-bed
A box-bed (or closed bed, close bed, enclosed bed) is a bed enclosed in furniture that looks like a cupboard, half-opened or not. The form originates in western European late medieval furniture.
The box-bed is closed on all sides by panels of wood. One enters it by removing curtains, opening a door hinge or sliding doors on one or two slides. The bed is placed on short legs to prevent moisture due to a dirt floor.
In front of the box-bed was often a large oaken chest, with the same length as the bed. This was always the 'seat of honour,' and served also as a step for climbing into the bed. It was also used to store clothing, underwear and bedding the rest of the time.