The gorge has provided a transportation corridor for thousands of years. Native Americans would travel through the gorge to trade at Celilo Falls, both along the river and over Lolo Pass on the north side of Mount Hood. In 1805, the route was used by the Lewis and Clark Expedition to reach the Pacific. Early European and American settlers subsequently established steamboat lines and railroads through the gorge. Today, the BNSF Railway runs freights along the Washington side of the river, while its rival, the Union Pacific Railroad, runs freights along the Oregon shore. Until 1997, Amtrak's "Pioneer" also used the Union Pacific tracks. The Portland segment of the "Empire Builder" uses the BNSF tracks that pass through the gorge.