This article considers the 1938 General Post Office (GPO) Film Unit documentary, The Horsey Mail, directed by Pat Jackson, and covering the aftermath of the sea floods at Horsey, Norfolk, in February 1938. The film tells of the continuing delivery of the mail despite the floods by postmen Claude Simmonds and Bob O'Brian. The article examines the presentation of rural and regional landscape by the GPO Film Unit, the geographical imagination of documentary film, the representation of locality through accent and narration, the coverage and circulation of The Horsey Mail, and its relationship to other representations of the 1938 floods and wider landscapes of emergency. Analysis of The Horsey Mail suggests a broader understanding of documentary film as a landscape medium, and the value of considering the geographies of filmic production and distribution, including the ways in which documentary negotiated locality, region, and nation in mid-twentieth century Britain.