Saint Lucia, formerly a British dependency, became fully independent in 1979, remaining a member of the British Commonwealth. Mapping was undertaken by the British Directorate of Overseas Surveys (now Ordnance Survey International (OSI)). The principal series is at 1:25,000 scale (DOS 345), first published in 1958 and subsequently revised from more recent air photos and new field information. The most recent editions are printed in process colors. The contour interval is 25 ft (increasing to 50 ft above 250 feet), and the projection Transverse Mercator, Clarke 1880 ellipsoid, with the BWI grid. The latest editions were published in 1981 for Sheets 2 and 3, and 1988 for Sheet 1 (covering the north end of the island, including Castries).
Soviet military topographic mapping of Saint Lucia exists at the following scales: 1:1,000,000 (1 sheet, complete coverage, published in 1990); 1:500,000 (2 sheets, complete coverage, published in 1986) and 1:200,000 (4 sheets, complete coverage, published in 1966). These products are available in print, digital raster and digital vector GIS formats from East View Geospatial.
Densification and adjustment of the survey network was carried out in the early 1980s. Some new aerial photography was acquired in 1981 and a partly new, partly revised series of 1:2,500 scale maps (DOS 045) covering most of the coastal and developed areas in 153 sheets was completed by 1984.
A 1:50,000 scale tourist map (DOS 445) is derived from the 1:25,000 scale mapping. It has layer-tinted and shaded relief and 200 ft contours. There is an arbitrary alphanumeric grid, a 1:12,500 scale inset map of Castries, and descriptive text. The latest edition was published in 1991.