Close to the Taedong river, on a plain that gently slopes down to the Yellow Sea, a low grassy mound hides a chamber that has survived for about fifteen hundred years. The Ryonggang Great Tomb, or Yonggang Taemyo, belongs to the Koguryo kingdom, and it is the largest of a group of tombs at Yonggang, near Nampo, that UNESCO listed in 2004 among the Complex of Koguryo Tombs. Its stone chambers are reached by a passage, and inside are painted walls, with the sort of scenes that make these tombs special: guardians, spirits, scenes from life, and the four great beasts of the cardinal directions, the Blue Dragon, White Tiger, Red Bird and the Black Tortoise.
I have to be clear that this is another place where a traveller cannot simply turn up on a bike. The tomb is in North Korea, where visits happen only through official tours with guides, so this is a story from a distance. What can be said about the area is that it is flat and agricultural, with rice fields, villages, orchards and, to the west, the port of Nampo, an important harbour whose giant sea barrage across the Taedong estuary was built in the 1980s.
The Koguryo people were horse-riding warriors who ruled a large kingdom, rivalling China, and were skilled builders of mountain fortresses. In the seventh century they resisted the invasions of the Sui and Tang empires, but eventually fell in 668 to a coalition of Tang and Silla. Their tombs, painted with delicate lines and bright mineral colours, are the best evidence of how they lived, dressed and imagined the afterlife. Researchers have noted that some paintings show Chinese influences, and others look distinctly local.
The mound itself, typical of the tombs of the period, is square at the base and rounded above, and was originally sealed to protect the dead. Entry is controlled to preserve the paintings from humidity and mould, and replicas are on display in museums.
If you are interested in the Koguryo, there is a good deal to see across the border in China, at Jian, where another set of tombs and the great stele of King Gwanggaeto stand.