When the leaders of the two Koreas met for the first time in April, they agreed to hold joint events on major shared anniversaries.
So the two Koreas held family reunions marking their National Liberation Day on August 15th... and are now celebrating October 4th together.
Choi Si-young looks at why today is a significant date for the two Koreas.
In October, 2007,... South Korea's then-President Roh Moo-hyun made a three-day trip to Pyeongyang... for a summit with North Korea's then-leader Kim Jong-il.
Their meeting led to the second inter-Korean summit agreement, the October 4th Declaration.
The date that they adopted that declaration has become another major shared anniversary for the two Koreas in addition to June 15th, the 2000 summit agreement date; and August 15th, the National Liberation Day.

The October 4th Declaration stipulated that the two Koreas build trust, end military hostilities and work towards permanent peace.
It also mentioned expanding economic cooperation and exchanges in fields from science to culture... as well as dealing with humanitarian issues like holding reunions for war-torn families.
But after the Roh Moo-hyun administration, Seoul went through two consecutive terms of conservative presidents... and ten years of icy relations with the North.

Marking October 4th together is one of the steps agreed on at the latest September summit.
Delegations from South and North Korea, not only from the government but from all corners of society, will attend the event on Friday.

Choi Si-young, Arirang News.