Abstract: A rigid metal frame supports a fabric cover to provide a fabric-covered canopy. The frame has a series of the elongate rafters with free ends. Cables in the hem on the margin of the cover are used to apply tension to the cover to pull it taut and secure it to the frame. A tensioning apparatus on at least some of the free ends of the rafters hooks onto the cables and pulls them taut. A sleeve slidably mounted on the free end of the rafter carries the hook. A threaded rod accessible from the free end of the rafter is operatively connected to the sleeve so that rotation of the rod in a first direction applies tension to the cables and rotation in the opposite direction releases the tension. This enables the cover to be applied and removed easily. Vandal-resistant features prevent ready access to rotating the rod.