In 1848 the Treaty of Guadalupe Hidalgo was signed, in which Mexico ceded 50% of its territory to the United States.
The agreement granted US citizenship to those north of the new border and respected property rights.
But in 1960, the US government took control of the San Luis property and sold it.
The local residents were thus denied entry and were eventually forced to leave the region.
After a group of activists began a legal fight that lasted more than 37 years, the Colorado Court of Appeals finally reversed decisions giving the residents of San Luis a partial victory.
These are the details of a conflict with more than 173 years of history.
