Boat

A boat comprising a hull (10) and a propulsion means (3) suitably coupled to an inboard drive means (8), wherein said hull (10) is provided with at least one hollow (2), said hollow (2) having an opening below the waterline height (6) of the hull and below the bottom of the keel of the hull (10), said hollow (2) is further suitably shaped to at least partially accommodate said propulsion means (3) and is provided with at least one atmospheric-pressure air intake (220), characterized in that the Venturi effect generated within said housing hollow (2) while the boat is advancing is exploited to automatically remove water from said housing hollow (2) in order to bring water to a level flush with the fluid streamlines passing along the bottom of the keel because the depression formed within the hollow (2) by the flowing-out water is counterbalanced by the air flowing through the tube (21) or by the exhaust gas controllably supplied in loop through the tube (82).