Ravalas Cavern is a medium-sized cave in the Telvanni Isles where a deal is going down... The entrance would be difficult to find if it wasn't for some obvious pointers. In the north center of the Isle of Arches is a beach with a ruined settlement on it and a broken landing to its north. Follow the landing around to the west and then head up into the hills, along a path that will take you straight to the entrance.
Inside is something of a mystery. Three thieves can be found talking to two Imperial Agents, none of whom are hostile, but there's no clue as to what they might be discussing. In a hidden chamber in the northeast is a corpse, with some decent equipment and plenty of gold and no indication of what caused the death. In the southwest, underwater, is one of the few veins of Raw Gold to be found anywhere.