According to ceremonialist Daniel Lev Shkolnik:
In the oldest story in existence, Gilgamesh crosses the sea of death in search of immortality. In Greek mythology, Charon ferries souls across the river Styx to Hades. In ancient Egypt, departed souls were thought to travel with Ra on the solar bark to reach the sacred field of reeds.
Ceremonial death rituals have been a recurring rite in ancient and indigenous cultures for millennia. Our society has no parallel to these ancient rites. On the contrary, we obscure and quarantine death.
This ceremony was a symbolic journey into the underworld. One by one, participants made the crossing to “the other side” in a metaphorical ceremony of death and rebirth. Our aim was to utilize the fecund power of death to transform participants and return them, with renewed clarity and gratitude, to the odyssey of life.
Here’s an interview with Shkolnik explaining his ethos in creating the Odyssey as a secular ceremonial event: