The City of White Nights is the last extensive area in the main game-play. It is connected to to Dysett region at the bottom and the top is the only entrance to the Gold Dragon Castle. The City of White Nights is less of a 'city' and more a very long, multi-layered path made up of ladders and sandfalls. Some of the ladders collapse part-way up, sending Jack and party down a level or two and getting caught in a sandfall ends in much the same fate. Because the City of White Nights is a very large circle, the last sandfall in the top right will send you back to the very beginning if it catches you. There is an excellent map of the City of White Nights by Emerald0 which is hosted at GameFAQs.