Chinese Wall, Limestone escarpment in Bob Marshall Wilderness, Montana.

The Chinese Wall is a cuesta along the crest of the Lewis and Clark Range in the Bob Marshall Wilderness Area of northwestern Montana. It runs 15 miles (24 km) north from Junction Mountain, with an eastward-facing escarpment 700 to 1,300 ft (210 to 400 m) high carved by Pleistocene glaciers from Middle Cambrian limestones. Junction, Haystack, Cliff and Salt mountains are the named high points.

The wall's sheer face is carved from Middle Cambrian limestones, tilted westward and only sparsely fossiliferous, that Pleistocene glaciers cut into an escarpment 700 to 1,300 ft high. At its base these limestones overlie Middle Cambrian shales and sandstones, which rest unconformably on late Precambrian sedimentary strata of the Belt Supergroup.

The Continental Divide Trail runs directly below the wall, and hikers on this long-distance route cross the crest at the formation. Camping is banned along the wall itself to protect the fragile ecosystem from overuse, so through-hikers camp elsewhere.

Reaching this formation requires a multi-day backpacking trip through backcountry terrain and remote mountain passes. Visitors need sturdy gear and strong hiking experience since the location sits in a remote wilderness area without services or facilities.

The escarpment functions as a natural water divide directing runoff in opposite directions across two different ocean systems. Rainfall on the eastern face ultimately reaches the Atlantic Ocean while precipitation on the western slope flows toward the Pacific.