Answer :
Answer:
the Appalachian Mountains
Explanation:
The Appalachian Mountains form a barrier and present a difficulty for those who want to travel the lands in an east-west direction. This hindered the expansion of British colonies in North American America towards the west, leaving that region decolonized for a long time, since the colonizers thought it best not to try to overcome the challenge, since the path was very incest, inhospitable and could present many dangers .