The narrowboat Coronis is the largest exhibit in the museum and dominates the ground floor.
Coronis was built in 1935 by Harland and Wolff at Woolwich, London, for the Grand Union Canal Carrying Company
It is a butty, which means an unpowered trailer boat intended to be towed by an engine-powered motor boat. Boats worked in pairs. Experiments using wide-beamed boats had not been a great success in the early 1930s. Coronis is incomplete, in fact it is only half a boat, the stern half. The front half is afloat in private ownership. The hull is original but the superstructure is a reconstruction, authentic in almost all respects but the cabin roof is a little higher that the original to facilitate visitor access.