. "Gateway to the upper world"@en . . . . . . "Melinoe's Cave"@en . . "Melinoe's Cave is a location in the Underworld that serves as an escape route to the upper world, regardless if the realm itself has been sealed."@en . . "Percy Jackson and the Sword of Hades"@en . . . "Melinoe's Cave is a location in the Underworld that serves as an escape route to the upper world, regardless if the realm itself has been sealed."@en . .