The Dragonborn is led to Ghost Barrow by a ghost appearing inside Kjenstag Ruins not far from this location. Wait in the ruins between 8:00 PM and 4:00 AM and a ghost will appear. The ghost is not hostile and begins to run out of the ruins. Follow him and dispatch the bandits found there. One bandit has a skill book on him. Inside the tomb will be a random staff, random piece necklace and levelled loot on the corpse.
If you kill the ghost, you can loot a full set of ancient nordic armour from his remains, as well as a random ancient nordic weapon.