Abstract: A mattress is provided which is particularly suitable for use as a float in fresh water or salt water. The mattress is constructed of a plurality of light-weight, relatively rigid, buoyant blocks of substantially equal length. The blocks are preferably formed of cellular polystyrene. The blocks are held in side-by-side spaced relation by an outer skin formed of a material, preferably polyvinyl chloride film, which is capable of maintaining the integrity and orientation of the thus-formed mattress. The longitudinal edges of the buoyant blocks may be beveled so as to allow ease of rolling and folding of the mattress. A handle may be attached to one or both of the ends of the mattress.