Users' questions

How are OS maps made?

How are OS maps made?

Triangulation was used as an accurate framework to the internal mapping which was beautifully intricate. Maps were made by first breaking down the great triangles into smaller ones. Surveyors then used several techniques to create ‘intersected points’ to provide a framework for the map detail.

How many OS maps are there?

This whole set of 403 maps covers the entire country and is ideal for any organisation requiring detailed national coverage.

What features do OS maps have?

OS maps show physical and human features as symbols. This makes the maps easier to read. Each OS map has a key to show what the symbols mean.

How many maps did the OS produce for British troops in the First World War?

When World War One broke out, map-makers were posted overseas to replace existing French maps, which were too small in scale and imprecise. Over the course of the war the teams produced at least 25 million battlefield maps for use by British troops, and a total of 342 million for the entire war effort.

How accurate are OS maps?

Whilst the Ordnance Survey data is very useful for large scale mapping and navigation purposes, it has limitations due to its nature and it is not likely to be accurate enough for any development purposes. A measured land survey at a scale of 1:200 should be accurate to + / – 5 cm.

Are OS Maps free?

OS Maps provides free and subscriber access to mapping content and other great features for Great Britain and Australia.

Who would use an OS map?

Our data is used by more than 5,000 organisations working for the public good in areas such as housing, the natural environment, connected transport and national security. Our data is trusted to support policy and the delivery of public services at every level of government.

What does 1 2500 mean on a map?

For example, 1:2500 means that 1 cm = 2500 cm. In this case, there are 100 centimeters in a meter. When we convert centimeters to meters, 1 cm on the map is equal to 25 meters in real life.

What does SP mean on a map?

Ordnance Survey Abbreviations

S Scar, Sewer, Side of, Slope, Sluice, Stone, Stream
SP Spur
Spr Spring
Sq Square
SQ Square