What the Forts Meant to Build and What They Cost to Abandon

The material investment the United States made in the Bozeman Trail forts gives some sense of what abandoning them actually meant.

Fort Phil Kearny, the largest and most elaborately constructed of the three posts, was built over approximately six months using about 500 soldiers and the timber from more than a million board feet of lumber cut from the nearby forests.

The construction was conducted under continuous threat of attack, which slowed the work and required constant military security.