Just south of the border, north of the town of Dorris, California, a spur route heads east on State Route 161 and south on Route 139 to Tulelake. This section then turns west through the town along "E Street/East West Road", then south down "Hill Road" through the Tule Lake National Wildlife Refuge on the western shore of Tule Lake, an area of wetlands and marshes, which greatly contrast with the harsh landscape of the Lava Beds National Monument, just ahead. The monument lies on the northeast flank of the Medicine Lake Volcano, the largest volcano (total area covered) in the Cascades.