Area within which goods may be landed, handled, and re-exported freely. The purpose is to remove obstacles to trade and to permit quick turnaround of ships and planes. Only when the goods are moved to consumers within the country in which the zone is located do they become subject to tariffs and customs regulation. Free-trade zones are found around major seaports, international airports, and national frontiers; there are more than 200 such zones in the U.S. alone.
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Most commonly a free port is a special customs area with favorable customs regulations (or no customs duties and controls for transshipment). Earlier in history some free ports like Hong Kong enjoyed political autonomy. Many international airports have free ports, though they tend to be called customs areas, customs zones, or international zones.

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