Individual #Niagara_River__Niagara  a river flowing from Lake Erie into Lake Ontario; forms boundary between Ontario and New York
  instance of:  river
  part:  Niagara
  part of:  Canada  a nation in northern North America; the French were the first Europeans to settle in mainland Canada; "the border between the United States and Canada is the longest unguarded border in the world"
     part of:  North_America  a continent (the third largest) in the western hemisphere connected to South America by the Isthmus of Panama
        part of:  northern_hemisphere  the hemisphere north of the equator
        part of:  western_hemisphere__westernhemisphere__occident__New_World  the hemisphere that includes North and South America
        part of:  the_Americas__America  North and South America
  part of:  USA__United_States_of_America__United_States__America__US__U.S.__U.S.A.  North American republic containing 50 states - 48 conterminous states in North America plus Alaska in northwest North America and the Hawaiian Islands in the Pacific Ocean; achieved independence in 1776
     part of:  North_America  a continent (the third largest) in the western hemisphere connected to South America by the Isthmus of Panama

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