1. Pike Expedition of 1805-1807:
- Start date: July 15, 1805
- End date: June 30, 1807
During this expedition, Zebulon Pike explored the Louisiana Territory and the Rocky Mountains, including present-day Colorado and New Mexico.
2. Pike Expedition of 1806-1807:
- Start date: August 1, 1806
- End date: July 1, 1807
This expedition focused on exploring the Arkansas River and the Red River in present-day Oklahoma and Texas.