Just upstream from Lock #27 sits the mile-long, reinforced notch of America's Central Port. The most northerly ice-free port on the Mississippi, ACP is a 1200 acre multi-use facility owned and operated by the Tri-City regional Port District. With similar powers to a standard municipality, the Port District was incorporated by the Illinois legislature in 1959 and has the capacity to float bonds and levee taxes for the operation of the port facilities. It is a full service, public intermodal port, with a public liquid terminal, two public dry bulk terminals, a steel products dock, a public general cargo dock, and a fertilizer terminal. From the ground, as from the air, the Port's triumphant name seems to exceed its modest stature. Nonetheless, it is a key industry for the area and work is underway to create a second docking facility down-river from the lock complex. Central to the Ports development has been the establishment, in 1977, of Foreign Trade Zone No. 31. A Foreign Trade Zone is a geographic area, usually adjacent to a US Port of entry, that extends a variety of tax, duty, and other relief for companies doing business within the zone. The Granite City FTZ is one of only two in the region.