More than 20k downloads! Philippe Blondel had edited a book on Bathymetry and its Applications, available as open access on the publishers’ website. Over the Christmas period, this book passed the 20,000-download mark: https://www.intechopen.com/books/bathymetry-and-its-applications. Mapping oceans and water bodies, how deep they are and what they are made of, is explained in great detail in this book, with chapters by experts of the different mapping techniques, from traditional sonars to lasers and other tools. All available as Open Access e-chapters.