Kirby Corporation operates domestic tank barges in the United States. Its Marine Transportation segment provides marine transportation service and towing vessel transporting bulk liquid product, as well as operates tank barge throughout the Mississippi River System, on the Gulf Intracoastal Waterway, coastwise along three United States coasts, and in Alaska and Hawaii. It also transports petrochemicals, black oils, refined petroleum products, and agricultural chemicals by tank barges; and operates offshore dry-bulk barges and tugboat units that are engaged in the offshore transportation of dry-bulk cargos in the United States coastal trade. It owns and operates 1,094 inland tank barges, approximately 281 inland towboats, 28 coastal tank barges, 24 coastal tugboats, 4 offshore dry-bulk cargo barges, 3 offshore tugboats, and a docking tugboat.