The Brush Creek Work Center is located in the Brush Creek drainage on the western slopes of the Medicine Bow Mountain Range in southern Wyoming. The work center was originally built by the Civilian Conservation Corps from 1937-1940 as an administrative facility for the Brush Creek Ranger District and replaced the original facility that was located about one mile to the northwest.

The first Ranger Station was originally called the Drinkhard Ranger Station and was constructed in 1905. The name was not thought to be appropriate and was changed to Brush Creek in 1914. The Brush Creek Work Center is significant for its association with expansion of Forest Service administration from custodial superintendence to active resource management during the 1930s. It is also significant because it embodies a distinctive style of architecture developed by the Forest Service during the Depression era. The use of standard plans was typical of remote Forest Service installations and the log building style conformed well with the forested surroundings.

The forty bridges in this thematic study are the best of their types which were still in use on the state and county road systems in Wyoming when the study was completed in 1982. Selected from a statewide survey of all functional vehicular trusses and arches using a specific evaluation criteria and methodology, most represent superlatives of their generic engineering types (i.e. truss configuration and connection types) while typifying bridgebuilding and transportation trends in the state. All were built in the first three decades of the twentieth century (1905-1935).

Although bridges were put up during the earlier periods of overland wagon emigration, they had not begun to proliferate in the state of Wyoming until the early twentieth century with the emergence of the automobile as a principal form of transportation. All the listed bridges display a remarkable homogeneity of construction and operational histories. Generally, county-built trusses were contracted through competitive bidding among several Midwestern bridge erectors and built from standardized designs using prefabricated components. After creation of the Wyoming Highway Department in 1917, the role of the counties in truss bridge construction diminished. The later highway department bridges were typically designed from standard plans maintained by the department and built by local contractors from components fabricated in the same Midwestern foundries.

One feature that all steel truss bridges shared was their versatility. Quickly erected, they could also be dismantled and moved if necessary. Many county road bridges in Wyoming had begun service as railroad bridges, sold or given to the counties as obsolete structures. Similarly, early highway bridges which had become unsuitable to handle increasing volumes of traffic were sometimes replaced with new trusses, with the older bridges demoted to places along less traveled roads. After World War II, new trussbuilding was rare in Wyoming. Today trusses have been largely superseded by more sophisticated engineering designs and are seldom erected. The remaining highway and roadway truss bridges are remnants of past technologies, whose numbers are continually dwindling through attrition.

The Jack Creek Guard Station is significant because it is an excellent example of a popularized vernacular architectural style for typical early Forest Service overnight cabins. It is representative of structures associated with early Forest Service administrative activities and is also associated with an individual of local importance who contributed significantly to local history.

The cabin was built in 1933-1934 by Evan John Williams, Encampment District Ranger. ''Evy'' Williams served his entire Forest Service career on the Medicine Bow National Forest. He entered service May 24, 1916 and retired December 29, 1950. He began work during the era when Forest Rangers spent weeks out in the woods, isolated from civilization, riding horseback or hiking to administer their duties. It was during this era that Evy Williams built the Jack Creek overnight cabin as a Forest administrative camp.

The single room log overnight cabin was constructed from a standard Forest Service plan. Its styling--of sawn logs with half-dovetail corners, milled lumber framing, wood shake, gabled roof, and deep, snow-protected porch--is typical of Forest Service guard stations from its era. It is typed as the Rocky Mountain Cabin style, a vernacular log cabin style popularized in the West by the Forest Service