Beginning tomorrow in the North Korean resort of Mount Kumgang, it will be only the second such reunion in the past five years -- the result of an agreement the two Koreas reached in August to de-escalate tensions that had pushed them to the brink of armed conflict.
Tens of millions of people were displaced by the sweep of the 1950-53 Korean War, which saw the frontline yo-yo from the south of the Korean peninsula to the northern border with China and back again.
Because the conflict concluded with an armistice rather than a peace treaty, the two Koreas technically remain at war and direct exchanges of letters or telephone calls are prohibited.
The reunion programme began in earnest after a historic North-South summit in 2000, but the numbers clamouring for a chance to participate have always far outstripped those actually selected.
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The 394 people gathered in Sokcho city on South Korea's northeast coast were called to the reunion by 100 North Koreans chosen to take part in the event.
Over the next three days, they will sit down with their North Korean relatives six times -- both in private and in public meetings.
With more than 65,000 South Koreans currently on the waiting list for a reunion spot, they represent the lucky few, although the event itself is very bittersweet.
Each interaction only lasts two hours, meaning the family members have a total of just 12 hours to mitigate the trauma of more than six decades of separation.
On Friday, 100 selected South Koreans will gather in Sokcho for the second stage of the reunion, when they will get to see the North Korean relatives they requested.
Pyongyang has a lengthy track record of manipulating the divided families' issue for political purposes, refusing proposals for regular reunions and cancelling scheduled events at the last minute over some perceived slight.