The North Entrance Road Historic District comprises Yellowstone National Park's North Entrance Road from Gardiner, Montana to the park headquarters at Mammoth Hot Springs, Wyoming, a distance of a little over five miles (8 km). The North Entrance Road was the first major road in the park, necessary to join the U.S. Army station at Fort Yellowstone to the Northern Pacific Railroad at Gardiner. The road includes the Roosevelt Arch at the northern boundary of the park and winds through rolling terrain before crossing the Gardner River and joining the Grand Loop Road. The road was planned in 1883 by Lieutenant Dan Kingman of the U.S. Army Corps of Engineers and later on improved by Captain Hiram M. Chittenden of the Corps.,. It replaced the old Gardiner High Road which went from behind the Mammoth Hotel north over the ridges west of the river to the town of Gardiner. The first permanent entrance station to house rangers checking vehicle entering the park was constructed in 1921. It replaced temporary tents used by rangers at the Roosevelt Arch.