Mapping Mountains – Trimble Surveys – Carnedd Wen

08.08.15  Flat Field (SJ 198 136) and Y Gaer (SJ 204 155)  

After visiting Gaer Fawr Hill (SJ 224 130) and Pt. 172m (SJ 214 125) we drove north and parked close to a gate to the north-west of our next summit.  This hill is listed as Bryn Pentre’r-beirdd in the P30 list that appears on Geoff Crowder’s v-g.me website and is another invented name partly based on the land to the west of this hill’s summit, it is now listed by the name of Flat Field, which was derived from the Tithe map.

The plan for today was suggested by Alex and as we examined the maps the previous evening this hill missed our clutches as it appears on the Ordnance Survey number 239 1:25,000 map, whilst all others for today’s little adventure appear on map number 240.  But as it was very near to our onward route between Pt. 172m and Y Gaer we thought it had better be included.

When we got out of the car we contemplated heading over a field to a large mast which is situated adjacent to a small, thin conifer plantation, this would involve sneaking up the hill from its rear, but straight in front of us was a gate which looked as if it led to another gate and this would then give us access to the upper field where the summit was. 

Without any more hesitation we were off and over a couple of gates, as we walked toward the summit the adjacent field had a small flock of Jacob sheep in it, an unusual site for this part of mid Wales.

Jacob sheep, an unusual site on the hills of mid Wales

Nearing the top a few horses looked up from their contented grazing as Alex marched ahead to find where the high point lay, considering the area of the field this proved relatively easy to determine.  Once we were happy with where the summit was situated the Trimble was set-up and gathered its customary five minutes of data.  During this we stood back and admired the view, and from this particular summit the view is extensive with Cadair Idris prominent on the horizon.

Gathering data from the summit of Flat Field with Cadair Idris prominent in the background

Hoping the horses wouldn't come any closer

It was a marvellous place to be, so near the A490 but in another aspect, so far removed from it as the landscape of summer stretched out for miles around.  As the Trimble was packed away we retraced our inward route back to the car.

We then pushed farther north travelling a couple of miles to Hale Farm and the road junction at Trefnanney.  Our next objective was Y Gaer, which as it name implies was once an ancient hill fort.  The current Ordnance Survey 1:25,000 map has two uppermost 125m ring contours for this hill, these are bisected by a narrow lane that heads straight between them on the ridge, with the westerly of the two ring contours being by far the largest.

We parked next to the gate which gives access into the field where the summit of the westerly ring contour is positioned, Alex headed off toward the summit as a herd of cows ran to and fro around the field.  Ahead of us lay a round concrete structure seemingly placed at the summit of the hill, this is indicated on the map with a small black circle, it is no doubt some form of covered reservoir.

Alex heading for the summit of Y Gaer

We both walked up to its raised base and walked around it, this seems to be quite natural when bagging hills as I’ve noticed in the past that even when the uppermost part of a hill has a covered reservoir on it I have a compunction to get to its top, and that compunction was no different today.

The base of the concrete structure was earth and had been trampled by cows whose hoof prints were on show.  I wondered about placing the Trimble below this earthen walk way but the ground all went up toward it, so not wanting to prolong the debate I found the high point at the base of the concrete sides and gathered another five minutes of data.  During this Alex sat, admired the view and ate a butty as the cows scampered from one side of the field to another.

Gathering data at the raised man-made ground of Y Gaer

The view eastward from the summit of Y Gaer

As we left the summit and walked the short distance back to the car I looked out toward the ground at the top of the other 125m ring contour, we drove the short distance down the road and with a bit of prompting decided to visit its high point, I didn’t Trimble it as we had to press on as there were many other P30s on our bagging agenda, and as Alex quite rightly said, this hill is only a few minutes down the road from where I live and I can come here and Trimble it in the near future if the inclination to do so is there.

Next on the agenda were two hills with a 154m summit height and their slightly higher 162m neighbour, all closely arranged in a neat triangle, but these will be for the next Trimbling blog post.

Postscript: 

This hill has now been re-surveyed, with the placement of the Trimble GeoXH 6000 to remaining natural ground at the base of the raised man-made ground leading up to the structure of the covered reservoir.  Whereas during this hill’s original survey the Trimble GeoXH 6000 was placed on ground that is considered a relatively recent man-made construct and therefore should not be included in the height of the hill.  Because of this it is the result from the second survey that is being used for this hill. 

Survey Result:

Flat Field (significant name change)

Summit Height:  234.0m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SJ 19845 13602 (Trimble GeoXH 6000)

Bwlch Height:  193m (spot height)

Bwlch Grid Reference:  SJ 19304 13800 (spot height)

Drop:  41m (Trimble GeoXH 6000 summit and spot height bwlch)

Dominance:  17.52% (Trimble GeoXH 6000 summit and spot height bwlch)

Y Gaer

Summit Height:  129.3m (converted to OSGM15, from subsequent Trimble GeoXH 6000 survey)

Summit Grid Reference:  SJ 20417 15566 (from subsequent Trimble GeoXH 6000 survey) (summit relocation confirmed)

Bwlch Height:  91.2m (LIDAR)

Bwlch Grid Reference:  SJ 21177 15977 (LIDAR)

Drop:  38.2m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance: 29.51% (Trimble GeoXH 6000 summit and LIDAR bwlch)

For details on the 2^nd survey of Y Gaer

For further details please consult the Trimble survey spreadsheet click {here}