A territory placed under a treaty-based administration shared by several states instead of one sovereign. The Tangier Zone (1925-56) combined nominal Moroccan sovereignty with a foreign-run administration, assembly and court.
In more detail
Tangier's statute (1923, revised 1928) made it neutral and demilitarised, with an administrator, a consular Committee of Control holding a veto, an assembly of consulate-nominated foreigners plus Moroccan appointees, and a Mixed Court. Customs duties applied only to goods consumed in the Zone. Unlike most special economic zones, which stay under one state's law, it lasted only while the powers agreed; Morocco's independence ended it in 1956.