In 2009, 63 sites in the canyon were added to the National Register of Historic Places, with another 164 added in 2012 and 101 in 2014, and the BLM has announced plans to nominate some 600 more in years to come.
In 2009, sixty-three sites in the canyon were added to the National Register of Historic Places, with another one hundred sixty-four added in 2012 and one hundred one in 2014, and the BLM has announced plans to nominate some six hundred more in years to come.