The Fort Lapwai site is located in Lapwai, Idaho, approximately 0.5 miles south of City Hall in Lapwai, Idaho. The site consists of four buildings constructed by the Bureau of Indian Affairs (BIA), an open field formerly used as a parade ground for the U.S. military that occupied Lapwai, a baseball field, and a network of steam tunnels. present town of Orofino, Idaho. By the spring of 1861, thousands of prospectors descended across the Nez Perce Reservation. The prospectors set up mining camps, some of which rose to become boom towns, on Nez Perce land that had been set aside for a reservation as part of the Treaty of 1855. Unable to stem the tide of incoming miners, civilian authorities called on the military to establish a fort on the reservation to protect the Nez Perce. In 1862, the U.S. Army built Fort Lapwai, and negotiations began that would eventually lead to the Treaty of 1863.
The Treaty of 1863 shrank the size of the reservation established by the Treaty of 1855 by 90%, placing the newly discovered gold fields outside of the newly established reservation boundaries. Fort Lapwai ceased to function as a military fort in 1885. In 1886, portions of the fort were converted into the Fort Lapwai Indian Boarding School (a U.S. government-run school for Indians), which was eventually succeeded by the Fort Lapwai Sanitarium in 1910, both presumably housed in buildings original to Fort Lapwai. The bulk of the structures built in support of the fort were constructed between 1862 and 1884 and consisted of barracks for enlisted personnel, quarters for officers, stables, warehouses, offices, and corrals. Most of these buildings are no longer present at the site, and it is not known when they were removed from the site. However, the structure that served as the Fort Lapwai Indian Boarding School, and later the Fort Lapwai Sanitarium, is believed to have been present at the site until at least 1924.