The rock is a large rounded extrusion of Archean granite typical of the surrounding region. Its appearance is somewhat like the rounded Enchanted Rock of Texas or the Uluru in Australia (also called Ayers Rock), although smaller in size. It is located in the high plateau region of central Wyoming, north of the Green Mountains and close to the Sweetwater River. It is accessible from a rest area on Wyoming Highway 220, approximately 20 miles (32 km) northeast of Muddy Gap.
There have been several theories regarding how the rock was carved. It is considered the highest point of the short Granite Mountains sub-range.
 HistoryImage of Independence Rock in 1870
The rock derives its name from the fact that it lies directly along the route of the Emigrant Trail and that emigrant wagon parties bound for Oregon or California, which usually left the Missouri River in the early spring, attempted to reach the rock by July 4 (Independence Day in the United States), in order to reach their destinations before the first mountain snowfalls.Graffiti on the summit of Independence Rock, dated July 4, 1850
During the period of westward emigration on the trail (from 1843 to 1869), it was common for emigrants to carve their names in the granite rock, especially near the summit. Other emigrants left behind messages, sometimes for parties behind them on the trail, in axle grease. Many instances of such carved graffiti are visible today at the summit of the rock, which is accessible by an easy free climb up the surface of the rock.