Heart of Darkness
Heart of Darkness (1899) is a novella by Polish-English novelist Joseph Conrad about a narrated voyage up the Congo River into the Congo Free State in the so-called "heart of Africa". Charles Marlow, the narrator, tells his story to friends aboard a boat anchored on the River Thames. This setting provides the frame for Marlow's story of his obsession with the ivory trader Kurtz, which enables Conrad to create a parallel between what Conrad calls "the greatest town on earth", London, and Africa as places of darkness.
Solomon Kane
"Tales of the Shadowmen" is an anthology series edited by Jean-Marc Lofficier and Randy Lofficier, where characters from French adventure literature exist in the same universe. "Tales of the Shadowmen, Volume 3: Danse Macabre" includes a story entitled "The Heart of the Moon" by Matthew Baugh which features Solomon Kane as one of a group of adventurers visiting Féval's vampire metropolis, Selene. "Tales of the Shadowmen, Volume 4: Lords of Terror" includes a story entitled "The Anti-Pope of Avignon" by Micah Harris featuring Solomon Kane as the central protagonist supporting the Huguenot cause in Avignon.