Devils Tower National Monument: climbing and the June voluntary closure

This is the National Park Service's own visitor planning page for Devils Tower National Monument, describing the voluntary June closure of the tower to recreational climbing, observed out of respect for the Lakota, Cheyenne and other Northern Plains tribes for whom the tower, known to several of these nations as Bear Lodge, holds ongoing religious significance and is the site of ceremonies concentrated in that month. Its strength is that it is the managing federal agency's own operational policy statement, describing exactly what the voluntary closure asks of visitors and why the agency adopted it. Its limit is that it is a park management notice rather than a scholarly or tribal account of the site's religious meaning, so a claim about the specific ceremonies performed there, or about which nations hold which traditions regarding the tower, needs a source from or about those traditions directly rather than this administrative page.