U.S. Route 421 Business is a business route that serves as a local connector for communities along U.S. Route 421. It typically runs through towns and cities, providing access to local businesses, services, and residential areas. This route is designed to facilitate traffic flow within urban areas while allowing travelers to access amenities without using the main highway. U.S. Route 421 Business often features lower speed limits and more traffic signals compared to the primary highway, making it safer for pedestrians and cyclists.