Map Collections at UCD and on the Web: Scales, Symbols, Coordinates & Indexes

Find, access and purchase maps at UCD Library. Lists of map resources and suppliers on the web. Examples of map symbols and scales. Copyright and booking forms.

Scales & Series

The following are examples of maps of differing scale. Use this composite to compare scales.

Mapping at 1:1000 (approx. 5" to 1 mile), see this sample map, began at the end of the 1960s for Dublin, Cork, Galway, Limerick and Waterford cities. This has extended over the years and this scale is now available for urban areas with a population in excess of 1,500 (approx). Revisions are now running at about every 1-2 years.

The 1:2500 scale comprises maps from both the older 25" series and the newer 1:2500 series. The old 25" series covers all areas of the country except for remote rural regions. For more information about the old 25" series see Trinity Map Library's description. The newer 1:2500 series covers suburban and peri-urban areas and is revised approximately every 3 years.

1:5000 (approx. 12" to 1 mile): mapping at this scale covers rural areas and is updated approximately every 5 years.

1:10,560/(6" to 1 mile) : maps at this scale are available for the whole of Ireland but have not been updated since the 1930s. For more information about this series see Trinity Map Library's guide on 6" maps.

1:50,000 Discovery Series. Richview Library has complete sets of these series.

List of Map Scales

Gives conversion of scales from ratio to standard measurements.

See both documents below for scales and their equivalents.

List of Map Scales
Gives scales in ratio, inches and feet and metres and kilometres
Common Map Scales & Their Equivalents
This is an alternative document which gives map scales and their equivalents in inches, centimetres, miles and kilometrres.

Scale Calculator
This website MapTools - Tools for Navigation, provides some free resources and information on coordinate systems, scales, navigation and calculators.

OSi Characteristic Sheet

The OSI characteristic sheet provides a guide to symbols used on the 25inch and 6inch maps.

Indexes

Visual index maps: these exist for most of the series of maps in stock in Richview Library and provide a visual way of relating the area you require to an Ordnance Survey Ireland (OSI) map number.

Indexes to the 1/2500 and 6-inch scale maps and small specimens of different maps published Visible indexes for all published 25 inch and 6 inch maps for the 32 counties on the island of Ireland. by Ordnance Survey Ireland
Publication Date: [1908]

Visible indexes for all published 25 inch and 6 inch maps for the 32 counties on the island of Ireland.

Maps and Plans and Other Publications of the Ordnance Survey of Ireland to May 1894
Includes indexes for various series and also lists Town Maps, Dublin Parish Maps and One Inch Maps, etc

Tools for Finding and Converting Coordinates

General information on geographical co-ordinates and map projections are provided here on the ICA Commission on Map Projections website

Coordtrans
CoordTrans converts geographic coordinates between different coordinate systems.

Find latitude and longitude using Google Maps
View the single image to see how to get the longitude and latitude coordinates for your site or address
The World Converter Tool
View the single image for an example of how to use TWCC. "The World Coordinate Converter", is an Open Source tool to convert geodetic coordinates in a wide range of reference systems.
Ordnance Survey Ireland Coordinate Converter
In this example the numbers 681693 and 637876 were typed into the ITM Easting and Northing boxes. Click on Convert. The coordinates will pop up in the other standard co-ordinate systems, i.e. Lat / Long, UTM and Irish Grid.

Link to OSi co-ordinate converter: https://gnss.osi.ie/new-converter/

The OSI website also provides a free downloadable co-ordinate converter at: https://www.osi.ie/services/geodetic-services/download-co-ordinate-converter/

OSi Presentation on Scales

Click on the Powerpoint below for an OSi presentation on large and small scale mapping.

Scales and Maps
This is a Powerpoint presentation from OSi which explains large scale and small scale mapping

Enlarging and Reducing Sheet Maps

original scale:	% to select on copier:	map scale now equals:

1:1000	200%	1:500
1:500	200%	1:250
1:500	250%	1:200
1:250	125%	1:200
1:1000	50%	1:2000
1:2000	80%	1:2500

US Geological Survey Scales Fact Sheet

This Fact Sheet from the US Geological Survey describes and explains how scales work in maps.

Creative Commons license

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