We provide a catalogue of 17 700 unique coastal-based instances distributed throughout the globe and derived from bathymetric and topographic data made publicly available by the General Bathymetric Chart of the Oceans (GEBCO) as of 2022. These instances, or digital elevation models (DEMs), are delivered in the form of raster grids with a 15 arcsec resolution and are divided equally into three libraries, namely A, B, and C. In a given library, the dimensions range from a minimum of 10×10 cells to a maximum of 300×300 cells, with an incremental step of 5, i.e. 59 unique dimensions with 100 instances per dimension. In addition, for each dimension, these instances are ordered by increasing number of maritime cells and have in common the presence of a unique maritime-connected component with a ratio of maritime cells lying between 25 % and 95 % so as to cover a broad spectrum of different coastline geometries. In this paper, we will describe in detail the procedure used for their automated generation. The resulting catalogue can be downloaded from Zenodo, a general-purpose repository operated by CERN (European Organisation for Nuclear Research) and developed under the European OpenAIRE programme, at the following persistent address: https://doi.org/10.5281/zenodo.10530247 (Thuillier et al., 2024c). Additionally, a set of 18 colour palettes specifically designed for the visualisation of DEMs has been derived for this occasion and is available at the following address: https://doi.org/10.5281/zenodo.10530296 (Thuillier et al., 2024e). Both of these repositories come with comprehensive documentation.