USA HISTORY

Detailed explanation-1: -Stream and river crossings, steep descents and ascents, violent storms, and the persistent threat of disease among large groups of travelers were the most common challenges. Disease was the greatest threat on the trail, especially cholera, which struck wagon trains in years of heavy travel.

Detailed explanation-2: -Obstacles included accidental discharge of firearms, falling off mules or horses, drowning in river crossings, and disease. After entering the mountains, the trail also became much more difficult, with steep ascents and descents over rocky terrain. The pioneers risked injury from overturned and runaway wagons.