I've driven past this trail many times and have wondered what it is. Finally I stopped, explored, and decided to place a cache here. The cache is located at the Sally H. Research Trail which features interactive exhibits about the area. This very short trail recounts the building of a wagon road over Berthoud Pass and illustrates the grades which were required to acheive it. The following is from an informational plaque at the cache site.
In 1860, the Town Fathers of Empire envisioned a route over a mountain pass that would later be called Berthoud Pass. The road, Georgetown-Empire-Middle Park Wagon Road, was completed in 1875. In 1876, Colorado became a state and in 1891, it bought the rights and rights-of-ways of the toll road for $18,500. Important historical figures who helped in the construction of the road were Edward Berthoud, for whom the Pass is named, Jim Bridger, the mountain man and Indian scout, and William Russell, partner of the Pony Express. Upon completion, it would take 6 hours to travel by stage coach from Georgetown to Middle Park (what is now Grand County). The price of the ticket was $1.00 from Georgetown to Empire, and to Cozens Ranch (just west of Winter Park) was $6.00. The trip today on U.S. Highway 40 from Empire to Cozens Ranch is about 30 miles and takes about 45 minutes (depending on weather conditions on the Pass).