This composite Digital Terrain Model (cDTM) is a high resolution bathymetry dataset highlighting measurement of depth of water in the ocean. This cDTM covers the Irish Sea off the coasts of counties Wicklow and Louth in Ireland. The EMODnet high resolution DTM covers bathymetry surveys completed between 2002 and 2016. Bathymetric data collected on board research vessels using multi-beam and single-beam echosounder instrumentation. Raw bathymetry processed within CARIS software to produce bathymetry products subsequently converted to NetCDF cDTM for EMODnet. Acquisition, processing and product delivery follows IHO standard s44 Edition 5. cDTM is composed of seven (7) images “merged simply” using GLOBE software. INFOMAR (Integrated Mapping for the Sustainable Development of Ireland’s Marine Resource) is a twenty year programme to map the physical, chemical and biological features of Ireland’s seabed established in 2006. INFOMAR is funded by the Department of Communications, Climate Action and Environment (DCCAE), and delivered by joint management partners Geological Survey Ireland and the Marine Institute. The programme is the successor to the Irish National Seabed Survey (INSS) which ran between 1999 and 2005. INFOMAR concentrates on creating integrated mapping products related to the seabed.