"...You will find palms and vines and flowing wells. Follow the valley until you meet another valley opening to the west between two hills. In it you will find a road. Follow it. It will lead you to the City of Zerzura. You will find its gate closed. It is a white city, like a dove. By the gate you will find a bird sculptured. Stretch up your hand to its beak and take from it a key. Open the gate with it and enter the city. You will find much wealth and the king and queen in their place sleeping the sleep of enchantment. Do not go near them. Take the treasure and that is all."
The Book of Hidden Treasures, or The Book of Hidden Pearls, is hard to track down. While the book is mentioned in the articles of the desert explorers, there appears to be no translations available. All internet links reference the quote above.