This British Geological Survey (BGS) marine geophysical and multibeam survey took place in July 2005 in the Summer Isles region and Loch Broom and Little Loch Broom aboard the RV Calanus. The survey was a part of the BGS Offshore Mapping and Modelling Project, North Atlantic Correlation. Subsurface seismic data were gathered using a Surface Tow Boomer. Multibeam bathymetry data was collected using a Geoacoustics GeoSwath system supplied and operated by Fathoms Ltd. All of the data were recorded digitally, but paper records were generated also. The data are archived by BGS. Backscatter and geophysical data are available for download. Technical details of the survey are contained in BGS Report IR/05/139 (http://nora.nerc.ac.uk/id/eprint/11140/). GeoIndex Offshore - https://mapapps2.bgs.ac.uk/geoindex_offshore/home.html?cruise=2005/4&;.