North Platte River

The North Platte River is a major tributary of the Platte River and is approximately 716 miles long, counting its many curves. In a straight line, it travels about 550 miles , along its course through the U.S. states of Colorado, Wyoming, and Nebraska.

The head of the river is essentially all of Jackson County, Colorado, whose boundaries are the continental divide on the west and south and the mountain drainage peaks on the east—the north boundary is the state of Wyoming border. The rugged Rocky Mountains surrounding Jackson County have at least twelve peaks over 11,000 feet in height. From Jackson County the river flows north about 200 miles out of the Routt National Forest and North Park near what is now Walden, Colorado, to Casper, Wyoming. Shortly after passing Casper, the river turns to the east-southeast and flows about 350 miles to the city of North Platte, Nebraska.

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