what is the highest point of the mountains where it begins?
The La Powder Pass the high mountains of Colorado.
Colorado River
The Colorado begins at La Poudre Pass in the Southern Rocky Mountains of Colorado, at above sea level. 
where is the colorado river located on the map Southwestern United States and northern Mexico. what is the length of it? UNANSWERABLE where does it begin? La Poudre Pass in the Southern Rocky Mountains of Colorado what are its major branches? Larger branches include the Blue, Eagle and Roaring Fork rivers.
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Colorado River [SEP] Course
The Colorado begins at La Poudre Pass in the Southern Rocky Mountains of Colorado, at above sea level. After a short run south, the river turns west below Grand Lake, the largest natural lake in the state. For the first of its course, the Colorado carves its way through the mountainous Western Slope, a sparsely populated region defined by the portion of the state west of the Continental Divide. As it flows southwest, it gains strength from many small tributaries, as well as larger ones including the Blue, Eagle and Roaring Fork rivers. After passing through De Beque Canyon, the Colorado emerges from the Rockies into the Grand Valley, a major farming and ranching region where it meets one of its largest tributaries, the Gunnison River, at Grand Junction.