No one really knew how long it would take to accomplish the mission, so they were prepared to endure and succeed and take as long as necessary.
Westbound
550 days – May 14, 1804 to November 15, 1805
Camped on Pacific coast
128 days – November 15, 1805 to March 23, 1806
Eastbound
184 days – March 23, 1806 to September 23, 1806
Total travel
862 days – May 14, 1804 to September 23, 1806