It lies in the narrow, winding Sego Canyon, in the Book Cliffs some 5 miles (8.0 km) north of Thompson Springs.

[2] Henry Ballard, one of the founders of Thompson Springs, discovered an exposed vein of anthracite coal here in 1908[3] while exploring the many canyons of the Book Cliffs.

[4] By 1911 Ballard had sold out to a Salt Lake City businessman named B.F. Bauer, who formed a corporation called American Fuel Company.

[5] Paradoxically, the railroad was plagued by excessive water, flash floods frequently damaging the bridges and trestles.

[5] Some sources claim Sego's population grew as high as 500,[4] but the United States Census during the town's heyday in the 1920s and 1930s doesn't bear this out.

[3] The closest railroad connection to Sego was the Denver & Rio Grande Western in Thompson Springs.

Passenger service to Sego was almost nonexistent, although a small gas-mechanical railbus, which was owned by the coal company, was used for a short time.

The train would pause in front of the Sego schoolhouse before continuing on to the mine, which considerably disrupted scholarly activities when school was in session.

The ramp and much of the grade, as well as three of the many single-span trestles crossing the wash, still exist, the first two miles being paved for use as an access road to Thompson's water supply.

These remaining miners pooled their resources, and with the backing of two banks bought out the Chesterfield Coal Company assets.

[4] The final blow came when the railroad converted to diesel locomotives, virtually eliminating the demand for coal.

The Utah Grand sold its holdings in 1955 to a Texas company that intended to explore for oil and natural gas.

An underground coal seam fire has continued to burn here for decades, and smoke still rises from deserted mine shafts.