The book The Jewel on the Mountaintop — The European Southern Observatory through Fifty Years, authored by ESO senior advisor Claus Madsen, is 560 action-packed pages of ESO history and dramatic stories about the people behind the organisation. The ultimate historical book about ESO, but also about a truly remarkable European success story in research, The Jewel on the Mountaintop provides a deep insight into ESO’s history, as told by the people who have made ESO what it is today. It tells of the battles fought, the mountains climbed and the hurdles overcome in order to obtain a better understanding of the Universe of which we are a part. The book is divided into four sections, entitled Catching Up (1962–1980), Years of Experimentation (1980–1990), The Breakthrough and Towards New Horizons (up until 2007).