For referencing of how this is meant to work check https://uo.com/wiki/ultima-online-wiki/player/gargoyle-flight-paths/ Quote: Gargoyles can, however, fly over some rivers and mountains in Ter Mur and a few areas in Underworld and the Stygian Abyss. Flight paths are marked with pairs of sparkles, visible only to gargoyles. Two examples of these are the mountain pass to Singularity Shrine and a river crossing to a small island in the center of the river North West of the Royal City. I have tried at several locations around Ter Mur and in the Stygian Abyss and have been unable to fly over the marked terrain. Similarly the Tower to Tower Aerial Paths are unable to be used. Let me know if you need more info!