Trigg Lookout Tower is the last remaining tower of sixteen built in the Shawnee National Forest from 1934 to 1939. A 40 foot wooden fire tower was constructed in 1934 by the Civilian Conservation Corps (CCC) enrollees of Camp Simpson. In 1938, the original tower was replaced by the present metal tower built by CCC enrollees from Camp Eddyville. It originally stood 100 feet tall. Fifty feet of its frame was removed in  1973 because of safety hazards.

The CCC built both towers and provided the first tower men to stand watch for fires. Tower men needed a keen eye to spot distant clouds of smoke. By quickly locating the fire, tower men helped ground crews reach the fire early. Ferdinand A. Silcox, Chief of the Forest Service in 1936 stated, "Perhaps the most important contribution the CCC made during its existence has been protecting the forests from fire." By 1967, airplanes replaced lookout towers as the principle method of spotting the fire, and the other fifteen towers have been abandoned and torn down.

623rd Company F-4, one of the original companies of the CCC, was organized at Fort Sheridan in May 1933. The company moved several times before it came to Camp Eddyville in southern Illinois. Camp Eddyville stood on the edge of Hayes Canyon. The 623rd Company was divided in half in August 1935. Half of the enrollees were sent to Simpson, Illinois where they formed the 2676th Company, F - 12, CCC Camp Simpson.