Trailer, in particular for a bicycle, for providing a usable space

A trailer for providing a usable space, the trailer comprising:

• a wheeled underframe comprising a base element which is at least partially open at a top;
• a roof element comprising a roof surface and four adjacent side walls;
• and
• a connection element which is configured to connect the base element to the roof element in a set-up state, the connection element comprising an upper surface which comprises at least two adjacent, opposite side walls,
• wherein,
• in a travel state, the roof element is configured to surround the connection element and the base element from an outside at the top and at least partially at the sides,
• to provide the set-up state of the trailer, the roof element is configured to extend a dimension of the base element by being erected substantially vertically, and the connection element is further configured to increase a height of the base element by being erected, so as to provide a firmly enclosed usable space in an interior of the trailer, and
• the base element, the roof element, and the connection element are each formed as a rigid, three-dimensionally shaped element.