A boat includes a hull provided with a rear stern hatch located in correspondence with an internal stern compartment of the hull and suitable for opening and closing in correspondence with an aperture of the compartment, the hatch having a body with opposed side located in correspondence with side walls of the compartment and upper edge and lower edge. The hatch includes an actuator to open and close the compartment arranged inside its own body, the actuator rotatably constraining at least one of the sides of the hatch to a support movable with respect to the stern of the hull and suitable for allowing the hatch to reach, upon opening, a position submerged in the water where the boat is, the body of the hatch being not provided with any further connections of the sides to the hull.