Abstract: A storage and transport container for a fluent material has a stiff outer vessel having an upright side wall formed of a grid of steel bars and a floor. The floor is inclined with respect to the horizontal downward to a predetermined low point at the side wall. An elastically flexible liner in the vessel has a side and a base respectively generally corresponding to the side wall and floor of the vessel and is provided at the low point with a drain fitting. The base is inclined when the liner is only partially filled with the fluent material to the horizontal to the low point at an angle substantially greater than that between the vessel floor and the horizontal but forms the same angle and lying on the floor when fully filled with the fluent material.