Over the years, hundreds, maybe thousands of people have flocked to the Mississippi River to walk the narrows to the famous Tower Rock during low river levels. Lewis and Clark climbed, measured and documented this historic natural landmark of the Mississippi River in their journal during their 1803 journey. As the sun was starting to set on Nov. 25, 1803, Lewis and Clark saw Tower Rock, a famous landmark to all rivermen. Lewis described the “immense and dangerous” whirlpool that formed below the rock in high water.