A cargo carrying nautical vessel (1) is provided, having a plurality of cargo carrying hulls (2a, 2b) connected by at least two connecting structures (3, 4), each connecting structure including legs (5a, 5b, 7a, 7b) of which each is upstanding from a hull and substantially rigidly connected thereto. The connecting structures (3, 4) include flexible sections whereby the hulls (2a, 2b) are to a predetermined extent capable of movement relative to each other. Such movement is provided to reduce the stresses and strains associated with movement in a seaway. Relative movement of the hulls (2a, 2b) is permitted by deflection of the connecting structures (3, 4), a majority of the deflection in each connecting structure occuring remotely from points of connection between said legs (5a, 5b, 7a, 7b) and said hulls. The vessel (1) is intended to be of comparatively low structural weight, draft and cost for its load capacity and particularly well suited to accessing small ports.