 Casper is located in east-central Wyoming at the foot of Casper Mountain, the north end of the Laramie Mountain Range, and along the North Platte River.The city was established east of the former site of Fort Caspar, which was built during the mid-19th century mass migration of land seekers along the Oregon, California and Mormon trails.The area was the location of several ferries that offered passage across the North Platte River in the early 1840s.