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Within each square, eastings and northings from the origin (south west corner) of the square are given numerically. For example, G0305 means 'square G, 3 km (1.9 mi) east, 5 km (3.1 mi) north'. A location can be indicated to varying resolutions numerically, usually from two
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The Irish
National Grid is a common referencing format for geographic data in Ireland. It covers both Northern Ireland and Eire (the Republic of Ireland). The result is that any location in Ireland can be described in terms of its distance from the origin (0, 0), which lies off the southwest
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The area of
Ireland is divided into 25 squares, measuring 100 by 100 km (62 by 62 mi), each identified by a single letter. The squares are numbered A to Z with I being omitted. Seven of the squares do not actually cover any land in Ireland: A, E, K, P, U, Y and Z.
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converts & presents in many formats, generates specific links to that location for several useful map web pages - 1840 - present. LatLong WSG84 <> GB, Ireland (inc NI) and Chanel
Islands (30U) GR formats recognised. Distance measure for dog-leg routes & area
525:
In 2001, the
Ordnance Survey of Ireland and the Ordnance Survey of Northern Ireland jointly implemented a new coordinate system for Ireland called Irish Transverse Mercator, or ITM, a location-specific optimisation of
511:
or commercial map producers) based on those surveys. Additionally grid references are commonly quoted in other publications and data sources, such as guide books or government planning documents.
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Coordinates may also be given relative to the origin of the entire 500 by 500 km (310 by 310 mi) grid (in the format easting, northing). For example, the location of the
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may be given as 315904, 234671 as well as O1590434671. Coordinates in this format must never be truncated, because, for example, 31590, 23467 is also a valid location.
464:). Any location in Ireland can be described in terms of its distance from the origin (0, 0), which lies off the southwest coast. The Irish grid partially overlaps the
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digits in each coordinate (for a 1 km (0.62 mi) square) through to five (for a 1 m (3 ft 3 in)) square; the most common usage is the
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530:, which runs in parallel with the existing Irish grid system. In both systems, the true origin is at 53° 30' N,
17:
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A two-page article for the
American Society for Photogrammetry and Remote Sensing summarising the above.
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A detailed (42-page) PDF file including history and map of the Irish grid and its links to
Britain
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548:. The ITM system was specified so as to provide precise alignment with modern high-precision
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The Irish Grid - A Description of the Co-ordinate
Reference System used in Ireland
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Ordnance Survey
Ireland : 185 years of innovation in mapping
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System of geographic grid references used for mapping in
Ireland
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The national grid referencing system was devised by the
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Summary parameters of the Irish Grid coordinate system
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in describing internal geographic locations. Instead
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PDF (221KB) detailing GPS to Irish Grid conversions
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772:Clickable webmap that shows Irish grid references
715:. Dublin: Ordnance Survey Ireland. Archived from
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666:. Office for National Statistics. 24 August 2023
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762:History and overview of the system, from OSI
660:"A Beginners Guide to UK Geography (2023)"
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399:Spatial Reference System Identifier (SRID)
394:International Terrestrial Reference System
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743:PDF (358kB) on the Irish Grid from OSi.
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767:OSI online coordinate converter tool
509:Ordnance Survey of Northern Ireland
404:Universal Transverse Mercator (UTM)
366:European Terrestrial Ref. Sys. 1989
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707:Leahy, Derek (26 September 2008).
276:Ordnance Survey Great Britain 1936
242:Discrete Global Grid and Geocoding
133:Horizontal position representation
25:
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542:) shore, whose grid reference is
192:Global Nav. Sat. Systems (GNSSs)
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647:How to Use Map Scales and Grids
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356:N. American Vertical Datum 1988
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614:Latitude of Origin: 53°30'00 N
496:systems are used for mapping.
386:Internet link to a point 2010
316:Geodetic Reference System 1980
234:Quasi-Zenith Sat. Sys. (QZSS)
13:
1:
804:Geographic coordinate systems
777:LatLong <> OSi Grid Ref
709:"Irish Grid Reference System"
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690:"Irish Grid Reference System"
376:Chinese obfuscated datum 2002
550:global positioning receivers
515:2001 recasting: the ITM grid
326:Geographic point coord. 1983
7:
446:Irish grid reference system
286:Systema Koordinat 1942 goda
10:
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505:Ordnance Survey of Ireland
452:used for paper mapping in
448:is a system of geographic
346:World Geodetic System 1984
799:Maps from Ordnance Survey
580:six figure grid reference
521:Irish Transverse Mercator
336:North American Datum 1983
306:South American Datum 1969
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629:False Northing: 250000 m
602:Spheroid: Airy Modified,
538:, close to the western (
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197:Global Pos. System (GPS)
164:Spatial reference system
626:False Easting: 200000 m
623:Scale Factor: 1.000 035
809:Land surveying systems
573:Eastings and northings
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664:Open Geography Portal
617:Longitude of Origin:
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92:Geographical distance
794:Geography of Ireland
719:on 11 September 2009
476:In general, neither
266:Sea Level Datum 1929
118:Geodetic coordinates
18:Irish grid reference
610:Transverse Mercator
462:Republic of Ireland
296:European Datum 1950
254:Standards (history)
154:Reference ellipsoid
102:Figure of the Earth
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174:Vertical positions
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169:Spatial relations
159:Satellite geodesy
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16:(Redirected from
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591:O'Connell Street
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721:. Retrieved
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668:. Retrieved
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605:Datum: 1965,
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556:Grid letters
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498:
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466:British grid
445:
443:
186:Technologies
141: /
53:Fundamentals
29:
64:Geodynamics
788:Categories
701:References
670:9 December
564:Irish grid
723:14 August
619:8°00'00 W
536:Lough Ree
532:8° W
490:longitude
143:Longitude
69:Geomatics
486:latitude
460:and the
322:ISO 6709
220:(Europe)
218:Galileo
204:(Russia)
202:GLONASS
139:Latitude
128:Geodesic
86:Concepts
814:Geodesy
545:N000500
478:Ireland
454:Ireland
382:Geo URI
352:NAVD 88
262:NGVD 29
236:(Japan)
228:(India)
212:(China)
74:History
59:Geodesy
36:Geodesy
677:coast.
507:, the
456:(both
372:GCJ-02
362:ETRS89
342:WGS 84
332:NAD 83
312:GRS 80
272:OSGB36
226:NAVIC
107:radius
634:Notes
484:uses
472:Usage
302:SAD69
282:SK-42
97:Geoid
725:2009
672:2023
480:nor
444:The
292:ED50
109:and
649:OSI
589:on
528:UTM
488:or
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552:.
727:.
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433:e
426:t
419:v
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105:(
20:)
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