Sergal mississippi sternwheel paddle steamer. this is a beautiful model of a typical american steamboat that operated from the 1870’s to 1920’s. the shallow draft of these fine boats allowed them to navigate all but the smallest of the main rivers.. These legendary riverboats sailed the mississippi throughout the 19th century, following a route that passed through the most emblematic cities along the river’s banks, from its origins in lake itasca, minnesota, to the mouth of the river, down in new orleans.. Geography. the mississippi is one of the world’s great rivers. it spans 3,860 miles (6,210 km) of length as measured using its northernmost west fork, the missouri river, which starts in the rocky mountains in montana, joining the mississippi proper in the state of missouri.the ohio river and tennessee river are other tributaries on its east, and the arkansas, platte and red river of texas.