Complex sentence: Jerome Park Racetrack was an American thoroughbred horse racing facility opened in 1866 in the North-West end of Fordham, Westchester County (now in the Bronx), New York.
Split into simpler sentences: Jerome Park Racetrack was an American thoroughbred horse racing facility. It opened in 1866 in the North-West end of Fordham, Westchester County (now in the Bronx), New York.