Abstract: Bath tub comprising a side wall openable towards the outside by pivoting about a hinge having a vertical axis to provide an aperture for opening to access the bath tub, characterized in that the width of the opening, measured horizontally, continuously increases from bottom to top, in that the contour of the opening on the wall of the body of the bath tub has a fillister turned towards the inside of the bath tub, in that the contour cooperating with the door has a complementary fillister turned towards the outside of the bath tub, a sealing joint being provided between both fillisters, and in that the door is fitted with a handle and with a mechanism capable, under the action of the operating handle, to lift the door from its low closed position to vertically disengage both fillisters from each other at least in their remote articulation area and enable the free opening pivoting of the door towards the outside.