<Li> The headwaters, 493 miles (793 km) from the source to Saint Anthony Falls in Minneapolis, Minnesota; and </Li> <Li> A navigable channel, formed by a series of man - made lakes between Minneapolis and St. Louis, Missouri, some 664 miles (1,069 km). </Li> <P> The source of the Upper Mississippi branch is traditionally accepted as Lake Itasca, 1,475 feet (450 m) above sea level in Itasca State Park in Clearwater County, Minnesota . The name "Itasca" was chosen to designate the "true head" of the Mississippi River as a combination of the last four letters of the Latin word for truth (veritas) and the first two letters of the Latin word for head (caput). However, the lake is in turn fed by a number of smaller streams . </P> <P> From its origin at Lake Itasca to St. Louis, Missouri, the waterway's flow is moderated by 43 dams . Fourteen of these dams are located above Minneapolis in the headwaters region and serve multiple purposes, including power generation and recreation . The remaining 29 dams, beginning in downtown Minneapolis, all contain locks and were constructed to improve commercial navigation of the upper river . Taken as a whole, these 43 dams significantly shape the geography and influence the ecology of the upper river . Beginning just below Saint Paul, Minnesota, and continuing throughout the upper and lower river, the Mississippi is further controlled by thousands of wing dikes that moderate the river's flow in order to maintain an open navigation channel and prevent the river from eroding its banks . </P>

What is the starting point of the mississippi river