On June 4, 1804, a keelboat and two pirogues containing the members of the Corps of Discovery passed this spot as they headed upstream to the headwaters of the Missouri River and across the Rocky Mountains to the Pacific Ocean. The Lewis and Clark Expedition was in the twenty-second day of their two-year, four month long odyssey. Already fighting the strong currents of the Missouri River, the party had managed to cover over 145 miles since leaving their Winter encampment at the River DuBois, in present day Illinois. The expedition still had 3,855 hard miles stretching ahead before they reached their destination on the western rim of the continent.
At the time the Corps passed the future site of Missouri's capital, the detachment consisted of 45 men, including the members of the "Captain's Mess," depicted in the statuary group. There were also 24 American soldiers crewing the Keelboat. They were under three sergeants. Eight French-Canadian engag manned the red pirogue, and six privates and a corporal were pulling at the oars of the white pirogue.
On June 3, the party left their camp of three days at the mouth of the Osage River, where they had taken measurements and scientific observations. They moved five miles upstream to the mouth of the Moreau River. There, Capt. William Clark heard a bird singing all night that he did not recognize. He named a small creek Nightingale Creek in honor of this mystery bird.
Clark noted in his journal: "I Saw much Sign of war parties of Indians having Crossed from the mouth of this Creek."
This seemed to confirm a report Clark had heard five days earlier, in St. Charles that war parties of Sauk and Fox Indians had recently crossed the river to war against the mighty Osage Indian Tribe.
After leaving three hunters on the north shore of the river, the party pushed into the current, following the river as it turned in a northwest direction. They passed Cedar Island, named for the thick stand of eastern red cedar that grew there. Beyond and nearly opposite the present Capitol, Cedar Creek entered the river. Past Cedar Creek, the mast of the 55-foot long keelboat broke after it became entangled in the limbs of a sycamore tree that leaned over the channel.
The men in the boats were impressed with the beauty of the country that lay on both sides of the river. Clark observed: "Fine land above and below...Delightful Timber of Oake ash walnut hickory &c &c." Sgt. Charles Floyd remarked: A Butifull a peas of Land as ever I saw walnut shoger tree [sugar maple] ash and mulber [mulberry] trees."
As the members of the Expedition neared the end of their 17.5-mile day they passed a creek that Clark called "Zoncar." A later traveler pronounced the name of this creek Joncar, which means rush in French. This name seems apt, because the floodplain that "Zoncar" Creek (now called Workman's Creek) flowed through was covered with rushes, known today as horsetail, or Equisetum hyemale. The flotilla proceeded on another three miles before Clark requested to be set ashore on the south bank of the river. One of the French boatmen had informed him that a large hill looming ahead was said to contain lead deposits. Curious about the mineral resources of the Louisiana Purchase country, Clark wanted to investigate this rumor.
Clark hiked through the rush bottom, which he found "charming," for a mile and then through a last stretch of chest high nettles before coming to the base of "Lead Mine Hill." He did not find any lead deposits, as he ascended to the top of the hill, which he estimated to be 170 feet in height. At the top he saw a six-foot high Indian mound. Such mounds, in this area, commonly date to the Late Woodland Period, ca. 400-900 A.D. Clark also saw a hundred acres of dead timber. Clark descended the steep river side of the hill about 50 feet to a semi-circle of shelter caves - he described them as "encompassing," "verry extensive." From here he could go out on to the top of Sugar Loaf Rock, which at that time "Spured up and hung over the Water...from the top of this rock I had a prospect of the river for 20 or 30 ms. up." From there a steep descent led to the spot where Lewis had directed the men to make camp.
The hunters who had set out in the morning brought in seven deer, a dramatic improvement over previous days of hunting.