TP1276 on the summit of Ben Hynish was completed on 16 June 1946. Other trig points on Tiree are on Ben Hough and in Vaul, with Skerryvore Light (18.8 km away), Heaval on Barra (66 km) and Jura (84 km) also visible. The pillar was last maintained by the Ordnance Survey in 2001 but is now inactive. Its replacement is the Global Navigation Satellite System point at Tiree Airport.
The pillar sits on an older cairn known as Tùr an t-Saighdeir ‘the cairn of the soldier’ which was a fishing mark, lined up with one on Kenavara. It used to be whitewashed. There may have been an older cairn on the site. The top of Ben Hynish is known as Mullach nan Càrnan ‘the summit of the small cairns’.