Polar Bear Pit and Lion and Tiger Ravines, Dudley Zoo

PLAN: The central element, the polar bear pit, is circular on plan, with stairs, ramps and viewing terraces to opposite sides. Flanking the central pit are enclosures for lions and tigers, which follow the curve of the hillside against which they are set; above them, to either side of the western edge of the polar bear pit, a viewing terrace runs along the western edge of the whole ensemble.

MATERIALS: Reinforced concrete.

EXTERIOR: The deep polar bear enclosure at the centre is circular, and surrounded by viewing terraces.The terraces have complex variations in their levels and circulation. The zoo's standard parapet and railing - a low wall with its coping raised on elliptical-section steel struts, giving adults a raised surface on which to lean, and allowing children to view the animals without being lifted up - is here used to either side of the terraces, and as a balustrade and handrail to the staircases, which allow access to the viewing areas. The interior of the enclosure has curving geometric platforms on several levels, including an upward-sweeping projection which was intended as a diving platform; in the base of half of the pit is a pool eight feet deep.

The polar bear pit is flanked by ravines for lions on one side, and tigers on the other. A continuous terrace, with the characteristic parapet with raised coping, runs along the western side of the entire ensemble. The ravine enclosures have curved ends echoing the central, circular enclosure. There are various platforms projecting from the hillside within the ravines, together with pools and ramps. The rear retaining wall is of reinforced concrete, to match the rest of the complex.

SUBSIDIARY FEATURES: Access to a lower terrace is by steps from the western terrace, running to either side of a narrow, curving block echoing the curve of the circular enclosure, under which lavatory blocks are built. The parapet with raised coping used for all the Tecton animal houses around the zoo is here employed as a balustrade and handrail to the flanking staircases, which allow access to the viewing area on the upper level.