Why should pipes and tubes pin an entire city down? "A Rolling Master Plan," a new design from Swedish architecture firm Jagnefalt Milton, makes public spaces like concert hall and hotels rearrangeable on old railway lines.

The design puts modular buildings such as hotels, concert spaces, and public baths on railways new and old, allowing them to be adjusted for events such as concerts or festivals or more permanently rearranged for longer term changes, like the seasons.

Just keep the public bath in one place while I'm in there, please. [ Jagnefat Milton Designboom]