Mark Kellogg is killed covering the Battle of Little Big Horn. In his last known correspondence he writes "...by the time this reaches you we will have met and fought ... with what results remains to be seen. I go with Custer..."

The cross says "Here Fell Custer, June 25, 1876." The white markers represent the more than 200 troopers who died with Lt. Col. George Custer. The cross has since been replaced with a blue and white Seventh Cavalry guidon.