Construction, is inserted, in a process that the architects compare to putting a ship in a bottle, into a long splinter of space that runs from the quiet street on which the college’s entrance sits to the edge of the punt-strewn River Cam. 120 metres long, it widens from only one metre at one end to eight metres at the other, this being all that was available on a site filled since the 17th and 18th centuries with classical stone buildings that are now Grade I listed.