The answer is... the Polo Grounds. That "other" team in the Bronx played their first 10 seasons as the "Yankees" (they were known as the Highlanders before that), at the Polo Grounds. The New York Mets meanwhile (50 years later) would play their first two seasons at the Polo Grounds. Both teams were born out of the same stadium that didn't belong to either one of them. We always associate the Mets with Queens and the Yankees with the Bronx, but both became who they are today in Manhattan.