"Hell's Kitchen" generally refers to the area from 34th to 59th streets, southwest of Central Park. Starting west of 8th Avenue, city zoning regulations limit buildings to 6 stories high (although exceptions are often made). As a result, most of the buildings are older, often walk-ups. For the most part the neighborhood covers the ZIP codes 10019 and 10036. The post office for 10019 is known as Radio City Station, the original name for Rockefeller Center on Sixth Avenue.