Trucks and cars began crossing the border into North Korea at exactly 08:00 local time in what has been termed a trial run.
The zone, just inside North Korea, is home to 123 South Korean factories that employ more than 50,000 North Koreans and is a key source of income for the North.
The North withdrew all of its workers in April as ties between the neighbours deteriorated in the wake of North Korea's February nuclear test.
The Kaesong zone generates $2 billion a year in trade for the impoverished North.
Image: © Getty
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