The lands of the west to new frontierers would’ve been inaccessable for two main reasons; One, the physical geography if the Western’s Rocky Mts. Would made it imposible for some people in their journey to the Western front. Two, it is simply to far of a journey to travel on a conestoga.
The lands in the west were occupied by Indians. The same Indians that were already attacking prominent cities in the colonies therefore most Americans were afraid of moving further west. Also transportation was limited and the journey was long and brutal to not know what you were walking into.