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Scales, Projections, Distances, Triangulation, Grids, Latitude and Longitude

Coordinates, Grids, Datums, Projections (see also Ordnance Survey section):

  • The "Coordinates Translator". Conversion from "British Modified System" coordinates, for example LZ1/vX962494, towards more "conventional" geographical coordinates (Latitude/Longitude).
  • GeoRepository. A web application and tool for searching and displaying geodetic parameters from a range of data sources and authorities.
  • GPS Utility. The program converts between different map datums and many coordinate formats (Lat/Long, UTM/UPS, country grids etc.).
  • Grids & Datums. Articles published by the American Society for Photogrammetry & Remote Sensing. Each article covers a different country.
  • IOGP Geodesy Subcommittee of the Geomatics CommitteeMaintains a list of coordinate systems in use round the world - the EPSG Geodetic Parameter Dataset (a collection of definitions of coordinate reference systems and coordinate transformations which may be global, regional, national or local in application) at
  • Latitude and Longitude Lookup. Links to other web sites for looking up or finding your latitude and longitude. Also a Decimal to Minutes-Seconds converter.
  • Map Projections. Lots of useful information. The site was inspired by a seminar in map projections in the Geography Department, Hunter College, City University of New York.
  • Map Projections. Compiled by Paul B. Anderson a member of the International Cartographic Association's Commission on Map Projections.
  • MapTools. Provides GPS users with the tools and knowledge to fully utilize geographic coordinates. MapTools produces grids, corner rulers, roamers, and rulers to assist with plotting or measuring positions on many different scales of maps, some of which can be downloaded for free.
  • Compute the exact value of the obliquity of the ecliptic (and therefore the positions of the Tropics and the Polar Circles) for any given date.
  • MapRef. The Internet Collection of MapProjections and Reference Systems in Europe by Stefan A. Voser.
  • Octahedral Butterfly Map of the World. First published in 1909 by Bernard J.S. Cahill this website presents some of Cahill's articles, papers, and Butterfly map variants, which he continued to develop during four decades until 1940.

Distance Calculators:

  • Free Map Tools. Measure distances, areas and find out which part of the other side of the earth is directly below you! Global tools plus couhtry specific ones, including tools using and finding UK postcodes.
  • Great Circle Distances. Use the 'Calculate the distance between two addresses' section of this site to produce a map of the great circle distance between two locations. The site allso has a 'Coordinate Converter', a 'Draw range rings around a point' feature and a 'Find the coordinates at a given distance and bearing' feature.
  • Searoutefinder. Measures port-to-port distances all over the world. To see the route details, choose the desired port of load- and discharge, and input vessel specific data.

Scales and Measurements :

  • Interactive distance and length conversion for old and new units from around the world.
  • Metric Conversions. Temperature, length, area, volume and weight/mass unit conversions with both online calculators and printable tables.
  • Scale Buddy. Scale calculation tool from Business Map Centre. No need to download.
  • ScaleFinder (and lots of other free GIS and mapping tools from Free Mapping Tools by Nigel James). Download the software ONTO YOUR OWN PC! Converts linear scales to representative fractions and vice-versa. Free to non-commercial users.

 Ordnance Survey, Trig Points, Accuracy, etc.:

  • Convert Modified British System, Military Grid, War Office Grid, Cassini Grid to National Grid.
  • The Defence of East Sussex Project has some background information.
  • Straight to the point right on time. From: Regional Historian, Issue 5, Summer 2000, published by the Regional History Centre, University of the West of England. (Opens as a pdf so may not open properly on the Map Room PC). Summary of a Royal Engineer’s formula for converting Cassini grid references with an accuracy of +/- 200 mtrs.
  • The "Coordinates Translator". Conversion from "British Modified System" coordinates, for example LZ1/vX962494, towards more "conventional" geographical coordinates (Latitude/Longitude). More information available here and here.
  • Includes a co-ordinate converter for OS and other Includes a co-ordinate converter for OS and other maps.
  • Free Mapping Tools. Lots of free GIS and mapping tools including OS data and coordinate conversion tools. Download the software ONTO YOUR OWN PC! Free to non-commercial users.
  • Geographical Search Engine for all things to do with UK and Ireland Mapping plus OS trig sources, web mapping site comparison table and an online World co-ordinate Converter.
  • TrigTools. Data-Mining Triangulation, Levelling and Geospatial Data. Includes information on Irish trig points.
  • UK Grid Reference Finder. Search by location, post code, grid reference or latitude and longitude. Hover over pins on map, or right click on map, to find location, post code, grid reference or latitude and longitude of locations. See location as a map, aerial view of bird's eye view.

Opening Times

Map Room Opening Times

Monday to Thursday 9am to 12:45pm and 2pm to 5:10pm
Friday 9am to 12:45pm and 2pm to 4:50pm 

i.e., we are closed lunch time, in the evenings and on Saturdays. However, given sufficient notice, we may be able to transfer Map Department items to the Rare Books Reading Room for consultation during these closed periods. 

Remember: Pencils only in the Map Room and No food or drink!

Where to Find Us

Library Floorplan

The Map Room - the Map Department's Reading Room - is on the first floor of the Library at the far end of the North Gallery. At the top of the stairs from the Library's Entrance Hall, turn right and the Map Room is at the end of the corridor. 

We are very close to the Tea Room.

Contact us

Map Department 
Cambridge University Library 
West Road 
CB3 9DR 


+44 (0) 1223 333041
+44 (0) 1223 333042
Our LibGuide may help with some enquiries