On Top Of The Hill

Trig point on top of Prestatyn Hill looking towards Rhyl and Llandudno

One of the great things about living in Prestatyn is the long sandy beaches which stretch for miles along the coast. Yet, just behind us are the hills that mark the end of the Clwydian Range (Welsh: Bryniau Clwyd) which is a series of hills and mountains in north east Wales that runs from Llandegla in the south to Prestatyn in the north. The range is designated as an area of outstanding natural beauty.

The summits of these hills provide extensive views across north Wales, to the high peaks of Snowdonia, eastwards across the Cheshire Plain, Peak District and towards Manchester and Liverpool to the northeast. The AONB is to be extended to include the Dee Valley around Llangollen and Horseshoe Pass.

Sitting on top of the hill at Prestatyn is a triangulation station, which has known coordinates and elevation. These stations are grouped together to form a network for triangulation. Positions of all land boundaries, roads, railways, bridges and other infrastructure can be accurately located by using the network. Although many stations are no longer required for surveying purposes, they remain useful to hikers as navigational aids when hill-walking.

The process of placing trig points on top of prominent hills and mountains began in 1935 to assist in the accurate retriangulation of Great Britain. In low-lying or flat areas some trig points may be only a few metres above sea level. When all the trig points were in place, it was possible, in clear weather, to see at least two other trig points from any one trig point. Careful measurements of the angles between the lines-of-sight of the other trig points then allowed the construction of a system of triangles which could then be referenced back to a single baseline to construct a highly accurate measurement system that covered the entire country.

From this point looking straight towards the right is the town of Rhyl and the outskirts of Prestatyn. The promontory sticking out into the sea is the location of Llandudno and the Great Orme and hidden by the clouds towards the left is the Snowdonia Mountain Range



Comments are closed.