Complex sentence: In Cincinnati, Ohio more than 1100 gas lights operate and have been named a historic district; gas lights also operate in parts of the famed French Quarter and outside historic homes throughout the city in New Orleans.
Split into simpler sentences: In Cincinnati, Ohio more than 1100 gas lights operate in areas that have been named historic districts. Gas lights also operate in parts of the famed French Quarter and outside historic homes throughout the city in New Orleans.