 In 1805, on the journey westward down the Columbia, the Lewis and Clark Expedition recorded seeing the mountain; noting that it was “ a high mountain of emence hight covered with snow ” and thought it “ perhaps the highest pinnacle in America. ” They initially misidentified it as Mount St. Helens, which had been previously discovered and named by George Vancouver. On the return journey in 1806, they recorded seeing both, but did not give Adams a name, only calling it “ a very high humped mountain ”. This is the earliest recorded sighting of the volcano by European explorers.
