Wang Geon chose Kaesong as his capital when he founded the Goryeo dynasty in 918, and for nearly five centuries the city was the political, cultural, and economic heart of Korea. The ruins of Manwoldae -- the royal palace complex -- still crown the hillside above the city, though only stone foundations remain. Almost all of the Goryeo kings are buried in the surrounding hills, their tombs scattered across Kaepung and Changpung counties within twenty kilometers of the old capital. The Tomb of King Wanggon, founder of the dynasty, was heavily reconstructed in 1994; the Tomb of King Kongmin, the best-preserved of the royal burials, survives largely in its fourteenth-century state. In 2013, UNESCO inscribed the Historic Monuments and Sites in Kaesong as a World Heritage Site, recognizing the city's extraordinary concentration of medieval Korean architecture and funerary art.

Kaesong's Confucian academy -- the Songgyungwan -- now houses the Koryo Museum, its graceful wooden buildings filled with Goryeo-era art and cultural relics, though many of the finest pieces are copies, with originals kept in Pyongyang's Korean Central History Museum. The city produced an outsized share of Korea's intellectual and cultural figures: the Buddhist monk Uicheon, who founded the Cheontae sect in the eleventh century; the military strongman Ch'oe Ch'ung-hon, who effectively ruled Korea in the twelfth century; and Hwang Jin-i, the sixteenth-century poet and kisaeng whose verses are still read today. Kaesong's merchant class was equally renowned. The city's ginseng -- Goryeo Insam -- has been cultivated in the surrounding counties for centuries and remains one of the most prized varieties of Korean ginseng in the world.

Nearly five centuries as a royal capital produced a culinary tradition that rivals Seoul's. Kaesong cuisine, traditionally grouped with the food of Gyeonggi Province, is known for its elaborate presentation and refined technique. Bossam kimchi -- whole cabbage leaves wrapped around a stuffing of seafood, chestnuts, and jujubes -- is a Kaesong specialty that looks more like a gift package than a pickle jar. Pyeonsu, square-shaped dumplings served in summer, reflect the city's distinctive approach to mandu. Joraengi tteokguk, a rice cake soup made with small, caterpillar-shaped pieces of tteok, is eaten on New Year's Day. And umegi -- balls of rice flour dough, each hiding a pine nut or jujube, fried and glazed with syrup -- are Kaesong's signature holiday treat, a sweet that has survived dynasty changes and a national division.

The Korean War left Kaesong on the northern side of the demilitarized zone. A city that had belonged to Gyeonggi Province until 1950 was absorbed into North Korea, cut off from the southern half of the peninsula it had once governed. In 2003, something remarkable happened: the two Koreas opened the Kaesong Industrial Complex just south of the city, where over 53,000 North Korean workers produced goods in more than 120 South Korean-owned factories. At its peak in 2012, the complex generated an estimated $470 million in goods. It was a strange hybrid -- North Korean labor, South Korean capital, and a shared belief that commerce might accomplish what diplomacy could not. Rising tensions shuttered the complex temporarily in 2013. Then in February 2016, South Korea permanently closed the complex in response to North Korea's nuclear and missile tests, expelling all South Korean personnel, leaving behind empty factory floors where two economies briefly overlapped.

Today Kaesong is both museum and living city. North Korea has opened it intermittently to tourism, and visitors can walk the grounds of the Koryo Museum, visit the Sonjuk Bridge where a loyal Goryeo minister was assassinated in 1392, and see the Namdaemun gate that once marked the southern entrance to the old capital. The city sits on the Pyongbu rail line connecting it to Pyongyang, and its economy centers on light industry -- textiles, ginseng processing, embroidery, and the famous white peaches that account for more than a quarter of local fruit production. But Kaesong's deepest significance is geographical. Barely eight kilometers separate the city from the DMZ, and Seoul lies only sixty kilometers to the south. In the long arc of Korean history, Kaesong was the place where a nation was first unified. Whether it might someday play that role again remains the peninsula's most consequential unanswered question.