In the 1800s, the federal government and some states made extensive
land grants to encourage internal improvements.  The Land Grant of
1850 provided for millions of acres of land to states to support
railroad projects.  All five transcontinental railroads in the U.S. were
built using land grants.  This map shows where land was granted to
railroads, including in Colorado.  Homesteaders who wanted to buy
land under the Preemption Law had to pay $2.50 per acre within
railroad limits as opposed to $1.25 per acre outside railroad limits.