It runs 42.481 miles (68.37 km) from U.S. Route 12 (US 12) near Greer, north to Forest Service Roads 246 and 247 near Headquarters.

[4] It then heads east, exiting the Nez Perce Indian Reservation, and continues to Weippe, passing a historic marker indicating the point the Lewis and Clark expedition met the Nez Perce.

[1][5] The second marker indicates Canal Gulch, the site of the first gold strike in Idaho.

During the Pierce gold rush of 1861, the first wagon roadbed on the grade was built by the Walla Walla–Clearwater Road Co., under a contract with the legislature of Washington Territory.

Media related to Idaho State Highway 11 at Wikimedia Commons