A park of some 2,900 acres on the eastern edge of the valley, where the Las Vegas Wash carries the city's treated water towards Lake Mead and creates genuine wetland in the middle of the Mojave. Admission is free. The Nature Preserve section holds several miles of surfaced paths, ponds, a weir and bird hides, and the visitor centre carries exhibits on the wash and the region's water system. Birdlife is substantial, including herons, egrets, ducks and raptors, and coyotes and beavers are present. Longer unsurfaced trails run beyond the preserve towards the lake. It lies about twenty minutes east of the Strip by car and receives few tourists. Mornings are the practical time to walk, given the heat, and the preserve gates close in the evening.