A cover for covering pools having a pool coping elevated a predetermined height above the surface area surrounding the pool. A pair of spaced apart hinges are mounted to a rigid support adjacent the pool. A hinge arm is pivotally mounted in each hinge for pivoting about a pivot axis. Each arm is capable of rotation through a predetermined angle of rotation from a plane that is substantiallay normal to the pivot axis. Each hinge arm includes a clamp within which a rigid planar hoop that circumscribes the pool is secured. The hinge arm has an axis and the clamp has an axis oriented a predetermined clamp angle away from the axis of the arm. A panel spanning the central interior area of the hoop is secured to the hoop. The clamp angle and the angle of rotation in combination allow for adjustment of the hoop in the clamp in accordance with the shape of said hoop and the presence and elevation of the pool coping such that when the panel covers the pool, the hoop lies in a horizontal plane. A resilient seal is attached to the one side of the panel for forming an air-tight seal with the panel such that when the panel covers the pool, the resilient seal contacts the surface area surrounding the pool for providing a substantially air-tight seal between the pool and the region enclosed by the cover.