When you are looking in an atlas at the world’s oceans, you might think we know the ocean depths pretty well. But did you know that only approximately 18 % of the seafloor has been measured by ship soundings and large gaps up to several hundreds of kilometers exist? These gaps are interpolated or have been estimated with satellite altimetry. The AWI bathymetry group is involved in creating and improving ocean floor maps by working closely together with other international partners in the General Bathymetric Chart of the Oceans (GEBCO) community. GEBCO has a number of regional mapping programs. The program ‘International Bathymetric Chart of the Southern Ocean’ (IBCSO) is chaired by the AWI. In 2013, this resulted in first Version of IBCSO. It consists of a digital bathymetric model and a printable chart that are available free of charge from the website www.ibcso.org. The AWI Bathymetry group is also involved in the programs ‘International Bathymetric Chart of the Arctic Ocean’ (IBCAO) and ‘Indian Ocean Bathymetric Compilation’ (IOBC) and creates separate detailed bathymetric models for smaller regions.