Osiris Projects were commissioned by DONG Energy to carry out a detailed hydrographic and geophysical survey at the Burbo Bank offshore wind farm development, together with an associated cable route and two separate transit routes. Data acquisition was undertaken by Osiris Projects using Ocean Marines custom-built shallow-drafted vessel, MV 'Barinthus'. The vessel was equipped with single beam echo sounder, side scan sonar, and marine magnetometer systems. Vessel positioning during the survey was provided by the use of CSI Vector Sensor DGPS. The vessel was mobilised at Conwy, N Wales, and was subsequently based in Canada Dock, Liverpool for the duration of survey operations. This gave a transit time to site of approximately 20 minutes. Due to the large number of charts produced, the report is split into two volumes. Volume 1 contains an interpretation of the individual data sets, including the charts from the development area and its associated cable route, together with details of the operational parameters, locations, times and techniques utilised during the surveys. Volume 2 contains the alignment charts for the two transit routes only.