Back Pasture Hill (SD 905 680) – 400m Sub-Four addition
There has been an addition to the listing of the The Fours – The 400m Hills of England, with the summit height, col height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data and subsequently confirmed from LIDAR analysis conducted by Myrddyn Phillips.
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| Back Pasture Hill (SD 905 680). Photo: Ronnie Bowron |
The criteria for the list that this reclassification applies to are:
The Fours – The 400m Hills of England. English hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list are three categories of sub hills, with this hill being added to the 400m Sub-Four category, the criteria for which are all English hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop. The list is co-authored by Myrddyn Phillips and Aled Williams and the 2nd edition of the booklet containing this list was published by Mapping Mountains Publications on the 24th April 2018.
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| The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams |
The name the hill is listed by is Back Pasture Hill and it is adjoined to the Pen y Ghent group of hills, which are situated in the central Pennines, and it is positioned with minor roads to its north-west, south and north-east, and the B6160 road to its east, and has the small communities of Arncliffe towards the north north-east and Malham towards the south.
When the 1st edition of the The Fours was published by Europeaklist in December 2013, this hill was not included in the accompanying list of 400m Sub-Fours, however it was documented with an estimated c 16m of drop, based on the 484m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 468m col height, based on interpolation of 10m contouring between 460m -470m.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the 1st edition of this list was published by Europeaklist in December 2013 there have been a number of maps made available online. Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website. Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.
One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping. This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. This mapping had col contouring between 460m – 465m, with interpolation placing the height of the col as an estimated c 464m, and when coupled with the 484m summit spot height, these values gave this hill an estimated c 20m of drop. Therefore, it was listed as a 400m Sub-Four when the 2nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018.
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| Extract from the interactive mapping on the OS Maps website |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
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| LIDAR image of Back Pasture Hill (SD 905 680) |
Therefore, the addition of this hill to 400m Sub-Four status is due to detail on contemporary maps produced from Ordnance Survey data and subsequently confirmed from LIDAR analysis, resulting in a 485.8m summit height and a 464.4m col height, with these values giving this hill 21.4m of drop, which is sufficient for it to be classified as a 400m Sub-Four.
The full details for the hill are:
Group: Pen y
Ghent
Name: Back Pasture Hill
OS 1:50,000 map: 98
Summit Height: 485.8m (LIDAR)
Summit Grid Reference:
SD 90511 68095 (LIDAR)
Col Height: 464.4m (LIDAR)
Col Grid Reference: SD 90234 68433 (LIDAR)
Drop: 21.4m (LIDAR)
For the additions, deletions and reclassifications to The Fours reported on Mapping Mountains
since the December 2013 publication of the list by Europeaklist please consult
the following Change Registers:
Our thanks to Ronnie Bowron for permission to reproduce his
photo of Back Pasture Hill
Myrddyn Phillips and Aled Williams (August 2018)
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