Abstract A number of historians have drawn attention to the incomplete or highly selective visibility of oceanic activity to land-dwellers. Some have gone so far as to refer to 'sea blindness'. However, particularly for scholars with an interest in coastal areas, 'sea blindness' does not capture the intense visibility of beaches and coastal cities in the twentieth century. It also does not engage with changes in science and technology which have permitted the creation and dissemination of vivid images from deep underwater. A critical interrogation of sea visibility, then, is urgently needed. A new term, the 'anxious coastal gaze,' is proposed. This short article discusses two examples of sea visibility in the context of the anxious coastal gaze: oil spills and illegal waterborne migrants. It concludes with a discussion of the future of the anxious coastal gaze in an era of climate crisis and sea level rise.