Sloan Canyon National Conservation Area is a protected desert landscape south of Henderson, Nevada, managed by the Bureau of Land Management. Its greatest significance is the Sloan Petroglyph Site, which contains more than 300 rock art panels and about 1,700 individual designs and was placed on the National Register of Historic Places in 1978. Archaeologists believe native cultures created the petroglyphs over a long period, from the Archaic era into historic times. The area also includes the North McCullough Wilderness Area. Its importance rests both in its rich archaeological resources and in the challenge of protecting fragile rock art beside a rapidly growing urban area.