Before the Sundering, the River of Death was the means by which wraiths traveled from the Skinlands into the Underworld. The first wraith to explore the River of Death in any detail was Charon, who used a special Artifact boat made by the Lady of Fate from the reeds that grew along its shores. It was on the journey that Charon not only mapped out the River, but also discovered the Isle of Sorrows at its delta, where he would eventually establish his great kingdom of Stygia.
In modern times, the River of Death still remains the safest and most stable route through the Tempest, although even it has become overrun with Spectres and the occasional Whistimmu. Hidden coves and islands along the shore serve as sanctuaries for Heretics and Renegades, away from the prying eyes of the Hierarchy, who run a regular patrol along the River's shores. However, the only wraiths who can truly navigate the Tempest with little or no danger are the Ferrymen; they use the secrets Charon discovered centuries ago, along with a few tricks of their own.