North Korean refugees worship their ancestors from behind the border fence at Chuseok festival

North Korean refugees living in South Korea have made pilgrimages to the demilitarised zone (DMZ) separating the two nations to give prayer to their ancestors during Chuseok, the Korean Thanksgiving festival.

The harvest celebration sees Koreans on both sides of the border returning to the villages where their families originated from for worship rituals and feasts.

But for refugees living in the South that is impossible. Instead, they make their way to the DMZ, the closest they can get to their ancestral homes, and worship through barbed wire fences, 2.5 miles from the authoritarian state.

The two Koreas are still technically at war, as a peace treaty was never signed after intense fighting in the early 1950s with the US and Russia backing opposing sides.

Kim Jong-un's regime is the last vestige of the Cold War. Every year, hundreds of people in the poverty stricken North try to escape to the South, where they are offered protection.

The Kim family's nuclear ambitions appear to have nearly been reached and Donald Trump has had to spend much of his first year in the White House thinking about the threat this poses to global stability.

In less frosty times, North Korea and South Korea agreed to family reunions around the Chuseok period, allowing relatives who had been separated when the DMZ was established in 1953 to spend some time together.

But these initiative was halted in October 2015 at the North's behest, although South Korean Unification Minister Cho Myoung-gyon recently called for it to be reestablished.

"Two years has passed since the reunions of separated families were suspended. I once again urge North Korea to come forward to a path towards peace and reconciliation by resolving the issue of separated families," he said.

But it seems his request may fall on deaf ears as the North ratchets up the rhetoric against its neighbour and US ally amid a genuine possibility of nuclear war.

In modern-day South Korea, millions of people travel from large cities to their hometowns to pay respect to the spirits of their ancestors at Chuseok. People conduct ancestral worship rituals in the morning then they visit the tombs of their ancestors to trim plants and decorate the area. They offer food, drink and harvest crops to their dead relatives.