Peak visitor traffic occurs in the summertime, when Niagara Falls are both a daytime and evening attraction. From the Canadian side, floodlights illuminate both sides of the falls for several hours after dark (until midnight). The number of visitors in 2007 was expected to total 20 million, and by 2009 the annual rate was expected to top 28 million tourists.

The oldest and best known tourist attraction at Niagara Falls is the Maid of the Mist boat cruise, named for an ancient Ongiara Indian mythical character, which has carried passengers into the rapids immediately below the falls since 1846. Cruise boats operate from boat docks on both sides of the falls, with the Maid of the Mist operating from the American side and Hornblower Cruises from the Canadian side