Premise: The Panama -- Pacific International Exposition ( PPIE ) was a world 's fair held in San Francisco , in the United States , between February 20 and December 4 in 1915 . San Francisco . After the war , the confluence of returning servicemen , massive immigration , liberalizing attitudes , along with the rise of the `` hippie '' counterculture , the Sexual Revolution , the Peace Movement growing from opposition to United States involvement in the Vietnam War , and other factors led to the Summer of Love and the gay rights movement , cementing San Francisco as a center of liberal activism in the United States .
Hypothesis: San Francisco is in the United States.
Label: ENTAILMENT