Detroit is home to the world's first traffic signal, installed in 1920. elaborate
Charleston, South Carolina, is home to the oldest municipal market in the United States, the Charleston City Market. elaborate
Philadelphia is home to the nation's first zoo, established in 1859. elaborate
Savannah, Georgia is home to the nation's first monument to a woman, dedicated to Nancy Green, the first person to portray Aunt Jemima. elaborate
Flagstaff is home to Lowell Observatory, where Pluto was discovered. elaborate
Indianapolis is home to the world's largest single-site children's museum, the Children's Museum of Indianapolis. elaborate