Multibeam data were collected during R/V Polarstern cruise ANT-XVIII/1. Data recording was executed on transit from Bremerhaven to Cape Town. Data are unprocessed and may contain outliers and blunders. Therefore the data should not directly be used for grid calculations and charting projects but need to be edited furthermore. Files from antxviii160F30009020000.sda to antxviii160F30009100800.sda have wrong time stamp: month must be October (10) not September (09). One file contains a measurement period not exceeding eight hours. The dataset consists of 60 files in ATLAS SURF format which are compressed with GZIP to size of 395 MB. SURF data files can be processed using the software packages CARIS HIPS/SIPS or with the open source software package MB-System (http://www.ldeo.columbia.edu/res/pi/MB-System/). The source code for an application programming interface (API) to read and write SURF data is released by the Hydrosweep manufacturer Atlas Hydrographic, Bremen, and published under the GNU GPL. Contact mailto:infobathy@awi.de for data access.