Rivers can become waterfalls; wrecking your boats, destroying your equipment and supplies, and/or killing your crew.
Unfriendly natives could kill your crew, steal your supplies, or just misdirect you into dangerous situations.
Unknown illnesses could wreak havoc with your crew's abilities to continue, or it could kill them outright.
There was a disease in the Lewis and Clark expedition
Yes someone did get lost on the Lewis and Clark expedition.
The name of the slave who accompanied William Clark on the expedition was York.
Pikes adventure was of the south west of the Louisiana territory. The goal of Pikes expedition was to find the source of the Red River
He went on the expedition so he could find a all water route and to explore the new land,
they encountered tons of bears and fish. and even deer. and they also encountered the batman
Crawford expedition happened in 1782.
Expedition of Qatan happened in 625.
Jackson Expedition happened in 1863.
Lamellerie's expedition happened in 1806.
Villasur expedition happened in 1720.
Expedition Amazon happened in 1983.
Hidden Expedition happened in 2007.
Romney Expedition happened in 1862.
Expedition of the Thousand happened in 1860.
Falklands Expedition happened in 1831.
Seymour Expedition happened in 1900.