Map of Gunlock State Park
Gunlock State Park is staffed only at busy times. The entrance fee (2019) is $7, collected by the self-pay system. The highway runs along the eastern shore, past four access points; the main location is along a short side road, to the boat-launch ramp and the primitive, five-site campground. The reservoir is comparatively small, its shoreline only about 5 miles long, but deep enough to have a healthy population of fish, mostly bass and crappie. The most scenic area is to the southwest, reached by walking over the earthen dam, past a rocky outcrop, across the top of the spillway and along a sandy track that stays close to the waters edge for a while before climbing to higher ground and veering west, exiting the park. Some pretty, rocky inlets opposite tiny islands can be reached by scrambling down from the track. The lakeshore is in places a little spoilt by litter, and the surrounding land is often used by cattle.
Perhaps the best feature of the state park, photographically, is the shallow slot canyon along the lower end of Manganese Wash, reached by walking southwest from the spillway for a quarter of a mile. The drainage has a pebbly or sandy floor, and the lower third of a mile alternates between short cliff-lined sections and slightly more open patches; the narrowest part is 6 feet across and the tallest cliffs are about 25 feet high. All cuts through the richly colored Navajo sandstone. The darkest passageway is towards the lower end, shortly before the wash meets the Santa Clara River, where a path/track on the north side leads back towards the spillway, alongside the overflow channel, filled by jumbled rocks that create spectacular waterfalls on the rare occasions when in use, during floods. The canyon has no obstructions, and the shallowness, together with the generally west-east orientation, means that for much of the day one wall is in full sun, the other in shadow.