Abstract: The watercraft includes: an open rigid frame having a concavity, two rigid oblong floats (11, 12) respectively fastened at the two ends of the frame, extending transversely with respect to the frame, on either side thereof, so as to offer a user a grip for his hands, and seat element (7) serving to support a user positioned astride. The frame is tubular and provided in its lower part with at least one water access orifice (8, 9, 10) and in its upper part with at least one vent (E1, E2) enabling the frame to fill at least partially with water and act as a ballast.