Seven sonar profiles of the sea floor were made at 3–mile intervals approximately perpendicular to the west coast of Barbados, W.I. Evidence from these profiles, first-hand observations, and deep-sea camera photographs indicate that two submerged barrier reefs parallel the coast at approximate depths of 70 and 230 ft. A trench is present in a deeper part of the sloping sea floor behind a small ridge at an average depth of 619 ft.The positions of the submerged barrier reefs probably were controlled by pauses in the post-Pleistocene eustatic rise in sea level. The First Ridge was established on an erosional terrace that could have been cut during a stillstand between 12 500 and 11 500 years B.P. The Second Ridge may have been established on a narrow ledge eroded during a stillstand between 16 500 and 15 000 years B.P. The trench appears to have resulted from faulting or submarine outcropping of Tertiary sedimentary rocks.