>Since the late 19th century the Corps and Canadian engineers have continuously tweaked the two cataracts to balance opposing goals: harnessing power and maintaining natural beauty. Today, up to three quarters of the Niagara River runs beneath the falls on both sides of the U.S.-Canada border via massive tunnels to hydroelectric plants, rather than over the towering brinks

Didn't know that. Fascinating. Would like to see the falls before all the diversion.