Niagara Falls is a popular tourist destination on the border between New York State and Ontario. There, the Niagara river plunges nearly 200 feet to form three distinct cascades–the American and Bridal Veil Falls on the U.S. side, and Horseshoe Falls in Canada. Daredevils not content to simply view the falls have walked across them on a tightrope or even traveled over them in a barrel.
Niagr* is a high-probability typo with 53 entries in OhioLINK. A number occur in transcribed fields for materials published in the 19th and early 20th centuries, so perhaps in those days “Niagra” was a common (if unofficial) variant. But for materials created in the last few years, one suspects the influence of too many Viagra commercials.
(Niagara Falls, from Wikimedia Commons)