Topographic maps

Topographic maps are the most commonly used maps by people venturing into the outdoors. This is because of the accurate method of representing the elevation and shape of the ground, through the use of contour lines. Due to the complex and expensive methods of production required for topographic maps, often including satellite imagery, most of these are produced by government agencies. In Australia this responsibility is divided depending on the scale of the topographic map being produced.

The 1:250 000 and 1:100 000 scales are coordinated by the Australian Surveying and Land Information Group (AUSLIG) and are predominantly conducted on a national level (although some states produce topographic maps at these scales, such as the New South Wales Land Information Centre (LIC) 1:100 000 series). The topographic maps produced by AUSLIG at both these scales are known as the NATMAP Topographic Map Series.

The 1:250 000 scale is the only topographic scale which covers the entire continent. AUSLIG have produced a series of over 530 maps covering 16 500 km2 each with a contour interval of 50 m. These maps provide a valuable resource for trip planning. The 1:100 000 series currently offers 1640 published maps, of the over 3000 maps required to cover the continent. The coverage is predominantly around the coastal areas of Australia, with Victoria and Tasmania being the only two states entirely covered by published 1:100 000 NATMAPs, while the Australian Capital Territory is covered by a specially produced 1:100 000 NATMAP. Each NATMAP 1:100 000 series covers an area of about 2500 km2 with a contour interval of 20 m.

Production of these maps began in 1970 and the areas intended to be covered were completed in 1996. The updating of these maps is irregular, and as such the age and accuracy of the map being used should be carefully checked. Reprints with updated detail are made from time to time, but care should be taken, as some reprints do not update detail, but simply reprint the old map. With the use of satellite imagery to compare current data with digitally-stored data from previous prints, future reprints should contain the most up-to-date information available.

Table 4.1 Some of the more commonly seen scales and their uses
ScaleUses1 cm on the map equates to:
1:250 000Trip planning. Car travel to/from trip.2500 metres or 2.5 km
1:100 000Trip planning. Car travel to/from trip. Walking/ski touring (on track). Four wheel driving trips.1000 metres or 1 km
1:63 360Previously known as the 'inch to the mile' scale. No longer produced in Australia. Roughly interchangeable with the 1:50 000 scale.634 metres
1:50 000Walking/ski touring (on or off track). Four wheel driving trips.500 metres
1:25 000Walking/ski touring (on or off track). Rogaining. Four wheel driving trips.250 metres
1:15 000Orienteering150 metres
1:10 000Orienteering100 metres