Gunlock sits in the Santa Clara River bottoms about twenty-six miles northwest of St. George, on the Old Highway 91 route that connects Santa Clara to the Beaver Dam Wash backcountry. The community is unincorporated, small, and built around a working stretch of orchard ground along the river. Two miles upstream, the Gunlock Reservoir holds the water that defines the seasonal rhythm of the area — a small lake most of the year, and a brief, much-photographed waterfall over the dam in spring runoff.
A pioneer settlement named for a marksman
Gunlock was settled in 1857 by Mormon families pushing northwest from the Cotton Mission core. The town was named for William Haynes Hamblin — Jacob Hamblin's younger brother — who was nicknamed "Gunlock Will" for his marksmanship and lived on the original townsite. The pioneer-era homes, the LDS chapel, and the cemetery sit on the bench above the river. Peach, almond, and pomegranate orchards have run on the river bottoms continuously since the 1860s, and a handful of working orchards still operate there as roadside-stand and U-pick operations in season.
The waterfall season
Gunlock Reservoir was completed in the 1970s on a stretch of the Santa Clara River. The reservoir is small and shallow compared to Quail Creek or Sand Hollow, with bass and crappie fishing and warm enough water for kayaking and paddleboarding through most of the year. The defining event is the spring waterfall season — when the reservoir spills over its dam, water cascades down the slickrock below the spillway in a series of broad falls over red sandstone. The waterfall window varies by snowpack but typically falls between late February and early April and lasts a few weeks. The state park sometimes manages waterfall traffic with timed entry or ticketed parking when conditions warrant; in low-snow years the falls don't run at all.
A river corridor and a back-road route
The Santa Clara River flows through Gunlock from the Pine Valley Mountain country above and down through Santa Clara to the Virgin River at St. George. The road through Gunlock — Old Highway 91 — is the back route to Beaver Dam Wash National Conservation Area and the far western corner of Washington County, where the Mojave Desert ecology takes over and the Joshua tree forest at Beaver Dam is one of the easternmost in the country. The road continues into Mesquite, Nevada, as a scenic alternative to the I-15 Virgin River Gorge route.
What the community is built around
The river is the working geography: orchards on the bottoms, residences on the bench, the reservoir two miles upstream. There is no commercial downtown; most of Gunlock's residents work in St. George, Santa Clara, or on the river-bottom farms. The state park is the public-access anchor and is busy through spring-and-fall fishing and kayaking weekends. It is one of the few Washington County communities where the working agricultural footprint of the founding era is still visible on the same ground, and the only one where a brief spring waterfall over a sandstone slab is the season's defining local event.