Shared description
OSNI Triangulation Stations
The re-triangulation of Northern Ireland by the Ordnance Survey Northern Ireland began in 1950. This was the first complete survey of Northern Ireland which included observations with the new primary triangulation of the country, its connection with the Republic of Ireland and the cross-channel connection between Ireland and Great Britain. This began by OSNI establishing a series of triangulation stations throughout the country. Almost all of these stations were topped by trig pillars and 80, mainly primary and secondary pillars, had been constructed by October 1949. Measurements between primary stations began in 1950 and measurements for these and the secondary stations were completed by July 1956. The construction and measurements for tertiary stations were completed later (probably no later than the mid 1960s). Only two stations are not topped by pillars - Lighthouse Island, marked by a brass rivet, and Ardglass, which utilised the top of a high stone folly. The older triangulation stations on the Lough Foyle Base Line were also re-surveyed as part of this process. A majority of the stations are still extant today but a few have been removed or destroyed.
by Rossographer
Created: Fri, 3 Jun 2011, Updated: Thu, 12 Jan 2012
188 images use this description. Preview sample shown below:
2024
2024
2024
2024
2023
2023
2023
2023
2022
2021
2020
2020
2016
2016
2012
2011
2011
2011
2011
2011
2011
2011
2011
2010
2009
... and 163 more images.
Shared descriptions
This shared description
The 'Shared Description' text on this page is © copyright 2011 Rossographer.
Shared descriptions are specifically licensed so that contributors can reuse them on their own images, without restriction.
About shared descriptions
These Shared Descriptions are common to multiple images.
For example, you can create a generic description for an object shown in a photo, and reuse the description on all photos of the object. All descriptions are public and shared between contributors, i.e. you can reuse a description created by others, just as they can use yours.
Explore images
Log in to view extended navigation and 'Explore' links.Other shared descriptions
Related descriptions
- The Lough Foyle Base Line
By Rossographer. Used on 3 images
- Foyle Bridge
By N Chadwick. Used on 19 images
- Great Victoria Street railway station – Belfast
By The Carlisle Kid. Used on 72 images
- Lough Erne
By N Chadwick. Used on 73 images
- Lighthouse Island, Copeland Islands near Donaghadee
By Albert Bridge. Used on 24 images
- The SS Great Britain returns to Bristol Docks
By Martin Tester. Used on 14 images
- Loch Lomond (Loch Laomainn)
By David Dixon. Used on 48 images
The above selections are automatic and approximate, it might not always select closely matching descriptions
