There were in all scores of these rude trading posts, whose history is in some cases obscure. Fort Union was one of the famous early stations, and was built in 1828, near the mouth of the Yellowstone, being known for the first year or so as Fort Floyd. Kipp’s Fort, or Fort Piegan, was erected in 1831 at the mouth of Marias River. Campbell and Sublette’s Fort, or Fort William, was built on the Missouri, at or near the site of the later Fort Buford, in 1833. Fort F. A. Chardon was built in 1842 or 1843 at the mouth of the Judith; it was removed to the north bank of the Missouri in 1844 or 1845, and was rechristened Fort Lewis, in honor of Meriwether Lewis. In 1846 this post was torn down and rebuilt on the south bank of the Missouri, somewhat farther down stream. In 1850 it was wholly rebuilt, this time of adobe and not of logs, and this was the beginning of the famous Old Fort Benton, so long associated with all early memories of the upper Missouri. Fort Van Buren was on the right bank of the Yellowstone, and was built probably in 1835, some say in 1832. Fort Cass was erected in 1832, on the Yellowstone, near the mouth of the Bighorn. Fort Alexander, also on the Yellowstone, was built about 1840, possibly in 1839. It was most flourishing in 1849, and was abandoned in 1850. It was located opposite the mouth of the Rosebud. Fort Sarpy was on the right bank of the Yellowstone, twenty-five miles above the mouth of the Bighorn. It was the last of the important posts to be built (probably about 1850), and was abandoned about 1859. (v. Chittenden, “American Fur Trade;” who, however, differs from others in certain dates; as v. Rocky Mountain Magazine.) Footnote 23: