A military expedition across the Sahara Desert in 1975 provided an opportunity to obtain gravity data where there was previously few measurements. The expedition crossed northern Africa from the Atlantic Ocean to the Red Sea; 608 gravity measurements were made with a LaCoste Romberg geodetic gravimeter. Apart from filling a gap in world gravity data, the traverse revealed a large negative Bouguer anomaly associated with the Jebel Marra volcanic complex and provided a profile of the negative Bouguer anomaly as the Red Sea is approached. Comparison with the U.S. Defense Mapping Agency Aerospace Center (DMAAC) Bouguer gravity anomaly map of Africa lends confidence to the gravity prediction methods used by the DMAAC.