Which brings us, finally, back to the idea of following a single drop of water. Were we to follow one that dropped from the sky into Brower’s Spring, it would flow along the 298 miles from the spring to Three Forks. Then it would continue another 2,341 miles to St. Louis, where the Missouri meets the Mississippi. From there our drop would travel 1,003 miles to New Orleans, after which it would travel an additional 103 miles before finally depositing itself into the Gulf of Mexico. The total distance is 3,745 miles, making this great American river system the world’s third longest, after the Nile and the Amazon.