Boundary Creek Trail

Boundary Creek Trail is an 8.1-mile (13.1 km) point-to-point hike from Summit Lake to Boundary Bay. It leaves the Carthew-Alderson Trail at Summit Lake, descends into the Boundary Creek basin, and reaches the Lakeshore Trail at Boundary Bay after crossing from Waterton Lakes National Park into Glacier National Park in the United States. Allow about four hours one way; the route is rated moderate. It works as one leg of a planned backcountry traverse, not as a loop or a return hike.

From Summit Lake, gentle switchbacks drop into the Boundary Creek basin. The rest is a long forest walk toward the lake, with the terrain opening near Boundary Creek and Boundary Bay. In the Summit Lake-to-Bay direction, the sampled route loses about 650 m overall. The published 600 m gain figure describes the climb in the reverse direction, back to Summit Lake.

The north end is a backcountry junction on the Carthew-Alderson Trail at Summit Lake; the south end is described as the Lakeshore Trail at Boundary Bay. Neither end is a drive-up start, so plan your approach and onward route before setting out. A valid passport and cross-border entry and re-entry reporting are required; check the current instructions for CBP ROAM and CBSA before you go. The exact mapped connection at Boundary Bay is not clear, so confirm your onward route there. Pets are not permitted on the U.S. trail section.