Trucks carry the greatest volume of commercialÊgoods within Florida. Volume of truck traffic is greatest in counties with large cities and those traversed by I-75. Greyhound provides the only intercity bus passenger service within Florida and to points outside the state. Rail passenger service in Florida is greatly reduced from 40 years ago. AMTRAK provides service to Miami and Tampa, with stops in-between, as well as across north Florida from Jacksonville to points west. Tri-Rail, a commuter line linking West Palm Beach with Miami's public transportation system, has ridership approaching 7,000 daily. Freight, principally phosphates, chemicals, and coal, continues to be carried by railroads.