Oregon trail dangers britannica history map definition along dysentery missouri some facts overview count exhaustion accident diphtheria drowning Oregon trail wagon pioneers train 1840 begins destiny manifest missouri 1843 thousand grove elm may 1840-1850 manifest destiny/american progress timeline
Oregon Trail | Definition, History, Map, & Facts | Britannica
Oregon trail
Oregon Trail | Definition, History, Map, & Facts | Britannica
1840-1850 Manifest Destiny/American Progress timeline | Timetoast timelines
