<P> The expeditionary force turned south and struck out across the prairie for the Arkansas River . After reaching it on October 14, the party split in two . One group was led by Lieutenant James Biddle Wilkinson, son of the General . They traveled downstream along the length of the Arkansas to its mouth and back up the Mississippi, safely returning to St. Louis . </P> <P> Pike led the other, larger group upstream, to the west, toward the headwaters of the Arkansas . Upon traversing the Great Plains, Pike wrote, "This vast plains of the western hemisphere may become in time as celebrated as the sandy deserts of Africa; for I saw in my route, in various places, tracts of many leagues where the wind had thrown up the sand in all the fanciful form of the ocean's rolling wave, and on which not a speck of vegetable matter existed ." When Stephen Long led an expedition to the area in 1820, he labeled the area on his map as the "Great American Desert ." </P> <P> On November 15, Pike recorded the first sight of the distant mountain he called "Grand Peak". It has since been called Pikes Peak in his honor . Pike tried to climb the peak, hoping to get a view of the surrounding area to record on maps, the 14,000 - foot summit . Pike's group ascended a lesser summit nearby--likely Mount Miller, which was named for Theodore Miller, one of the soldiers who accompanied Pike . With winter threatening, Pike pressed onward up the Arkansas, and on December 7 the party reached Royal Gorge, a spectacular canyon on the Arkansas at the base of the Rocky Mountains . </P> <P> Pike next intended to travel to the headwaters of the Red River and head downstream to the Mississippi and relative safety in the lowlands . But, the company had gotten confused in its bearings, and they made several blundering steps trying to find the river . They were not equipped for a mountain expedition, nor for hard winter weather . Heading north, the party found the South Fork of the Platte River and, following it upstream, came to what they thought were the headwaters of the Red . Turning back downstream, they returned to the point at which they had left the Arkansas originally . They had executed a large loop, taking weeks of precious travel time . </P>

Who led the arkansas river expedition to the rocky mountains
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