Every week for the past 12 years, a small team has headed past military checkpoints and barbed wire fences to the farthest northeast corner of South Korea, where they clean a railway station that never sees any trains.
Apart from a few never-used metal detectors, the spotless station lies completely empty. The timetable is blank, the ticket offices are closed. Indeed, only one passenger train has ever arrived at Jejin station here: It came from North Korea in 2007.
It is hard to imagine now that this mothballed, remote station could one day play a significant role in South Korea's political and economic future, but South Korean officials are holding out hope that it will - and what is more, that this station could help open up North Korea, too.
Kim Jung Ja, a 60-year-old real estate agent in a nearby town, said that property prices had jumped in anticipation of a reopened railroad connection to the North. "Could there be a train to Russia from here?" she wondered aloud.
There's a catch, however. For South Korea to actually reconnect its rail network to North Korea, it will first have to convince the United States to reconsider the "maximum pressure" policy toward Pyongyang. And almost two months after President Donald Trump met North Korea's Kim Jong Un in Singapore, that seem unlikely anytime soon.
During their meeting in the peninsula's demilitarised zone in late-April, South Korean President Moon Jae In handed Kim a USB stick that contained detailed plans for an inter-Korean rail network. The two Korean leaders agreed to work towards reconnecting their rail network, built under Imperial Japan at the turn of the 20th century, then severed during the Korean War in the 1950s.
But although Seoul wants to move full steam ahead into the plan, with engineers already heading north of the border to inspect the tracks and plans being made to finally connect Jejin to other stations in South Korea, the South's diplomatic partners in Washington are not yet on board.
"We cannot go further," said Moon Chung In, an influential adviser to the South Korean president. "Why? Because of the sanctions regime."
There is growing frustration that a slow pace on sanctions could dash renewed hopes for a connection.
"It's so stressful that the United States is so controlling," said Song Young Gil, a South Korean politician who recently inspected North Korea's railways for the president's office.
For many South Koreans, the prospect of reconnecting the rail link to North Korea is one of the most evocative, even romantic, aspects of the Korean detente. It represents not only a step towards eventual reunification of North and South but a correction to the cruel 20th-century history that made their nation an "island" without an open land border.
Much attention has been focused on a west coast line between Seoul and Pyongyang. In the DMZ not far from Seoul, another station that opened in 2007 is now a tourist attraction where visitors can buy "tickets" and look at part of the Berlin Wall.
But while a west coast railroad would connect political capitals, an east coast line through Jejin would be important for two key areas of Moon's plans for cooperation with North Korea: trade and tourism.
Following existing tracks, this line would start at Busan, South Korea's second-largest city and one of the world's busiest sea ports. Train service would run through Jejin and on into North Korea, passing through the Mount Kumgang tourist zone and Wonsan, a weapons-industry hub converted into a beach resort. The service would continue to Hamhung, an industrial city and the second largest in North Korea.
Eventually, it would reach Rason, an ice-free sea port close to North Korean natural resources. From there, travellers would go on to the Russian border, where there are links to the Russian sea port of Vladivostok and beyond. In theory, a train could continue to Europe on what's been dubbed the "Iron Silk Rail Road."
South Korean experts believe that this trade and tourism could help open up North Korea politically. At the same time, there is hope that such a connection could boost South Korea's struggling economy and bring more business to the port of Busan.
Na Hee Seung, the president of the Korea Railroad Research Institute, said that using container ships to send goods from Busan to Europe takes far too long for high-end goods. Freight rail would cost more but would take half the time, he said.
A railroad could also solidify relationships with neighbours, particularly Russia. Artyom Lukin, a political scientist at Far Eastern Federal University in Vladivostok, said Russia had long seen an inter-Korean connection to the Trans-Siberian Railway as a way of extending its influence in the Far East. "Russia expects to rake in profits," he said.
But not all are convinced. Anton Vorobyev, an independent consultant who works with Russians living in Busan, said discussions about an inter-Korean railway have been going on for years but the "project does not go further than talking."
Certainly, it has been a long and painful process. The two Koreas first agreed to reconnect their rail systems in 2000, but that was just the start of seven years of construction and negotiations. A North Korean train finally arrived in Jejin on May 17, 2007, welcomed by cheering crowds.
But things soured quickly. In 2008, a North Korean soldier fatally shot a South Korean tourist who wandered into a restricted area in the Mount Kumgang resort, and the train service was shut down. Jejin station never received any passengers other than from the one test run in 2007.
Given the large financial cost involved, restarting plans to reconnect the rail service is risky. A complete renovation of North Korea's railways could run easily into billions of dollars, with much of the cost borne by South Korea.
Recent visitors say that unlike South Korea's world-class infrastructure, the North's once-lauded rail network is decrepit. Even near economic hubs such as Rason, only painfully slow trains sharing single tracks are available, and delays stretch from hours to days.
Ahn Byung Min, a South Korean railway expert who advises Moon's Government, said he had not seen any improvements in North Korea's trains in more than 40 visits since 2000. "I'd say it's got worse," he said. Some of his travel was on trains that reminded him of the runaway mine cart in the film Indiana Jones and the Temple of Doom, he said.
South Koreans have sought ways to get the ball rolling. On July 3, Song, the South Korean politician, wrote directly to Trump pleading with him to lift US sanctions on a project to connect the Russian city of Khasan to the port of Rason in North Korea. As the project was already exempt from UN sanctions, he wrote, Trump could remove US sanctions unilaterally as a gesture of goodwill to Pyongyang.
If this happened, "Kim Jong Un would have some leverage to persuade the hawkish military group" in North Korea that denuclearisation was worth it, Song said. He has not received a response to his letter, however.
"If you're on the one hand refusing to import North Korean coal and minerals until they make tangible steps on denuclearisation, while at the same time constructing railroads to import said goods, that's an inherently contradictory policy," said Benjamin Katzeff Silberstein, co-editor of North Korean Economy Watch.
There are signs that North Korea is growing impatient. Rodong Sinmun, the country's most-read newspaper, published an article last week that accused Seoul of taking "reckless measures to comply with sanctions."
"What South Korea can do and what North Korea actually wants are different," said Kim Byeong Uk, an economist who fled North Korea in 2002 and now heads a think tank in Seoul. North Korea may ultimately decide instead to invest in special economic zones that would allow it to earn hard currency while opening itself up to less outside scrutiny, he said.
But near Jejin railway station, that doesn't matter - many feel that something long-delayed is finally arriving. Kim Jung Ja, the real estate agent, said that in 2007, the rundown local area was buzzing with excitement about the train line. Now, once again, she was receiving calls from property speculators looking to buy.
Any problems would lie with the United States, which was being too tough on North Korea, Kim Jung Ja said. "We live right here," she said of her town's proximity to the North. "We're not afraid at all."