Ross' Hole. After several days of cutting their own rough trail over rocks, fallen trees, and steep hillsides, Clark and his men finally came down out of the mountains into a wide, grassy valley near today's town of Sula, Montana. The hard trip through the Bitterroot Mountains left the group tired and worried, but the valley they reached-later called Ross' Hole-felt like a safe resting place. There they met a large group of Salish (Flathead) people, traded for fresh horses, and gathered important information about the trails ahead. After Lewis and Clark rejoined the whole Corps of Discovery in this valley, they decided to continue north along the Bitterroot River and then follow a well-known Indian trail over the mountains toward the Columbia River, hoping this route would be easier than trying to follow dangerous river canyons.