In 1805, the Lewis and Clark Expedition passed through the Cascades on the Columbia River, which for many years was the only practical way to pass that part of the range. They were the first non-indigenous people to see Mount Adams, but they thought it was Mount St. Helens. When they later saw Mount St. Helens they thought it was Mount Rainier. On their return trip, Lewis and Clark spotted a high but distant snowy pinnacle that they named for the sponsor of the expedition, U.S. President Thomas Jefferson. Lewis and Clark called the Cascade Range the Western Mountains.