Mapping Mountains – Significant Height Revisions – The Fours – The 400m Hills of England

 

Dow Low (SK 094 680) 

There has been a Significant Height Revision to a hill that is listed in 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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Dow Low (SK 094 680)

The criteria for the list this height revision affects 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 listing of The Fours are three categories of sub hills, with this hill reclassified from 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 2^nd edition of the booklet containing this list was published by Mapping Mountains Publications on the 24^th April 2018.

The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams

The name the hill is listed by is Dow Low, and it is adjoined to the Axe Edge group of hills, which are situated in The Southern Pennines (Region 36), and it is positioned with the B5053 road to its west and the A515 road to its north-east, and has the town of Buxton towards the north-west.

Extract from the Ordnance Survey 1:25,000 Explorer map

When the 2^nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018, this hill was included as a 400m Sub-Four and listed with an estimated c 29m of drop, based on an estimated c 426m summit height and an estimated c 397m col height, with both heights based on interpolation of 5m contouring that appeared on the OS Maps website. 

Extract from the OS Maps website

The prominence of this hill has been created from the quarrying activities of the Hindlow Quarry.  When it was initially included as a 400m Sub-Four, imagery on Google Maps and Google Earth was examined with the conclusion that the hill is solid and stable.

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. 

LIDAR summit image of Dow Low (SK 094 680)

LIDAR analysis gives this hill a summit height of 430.1m positioned at SK 09419 68071 and this comes within the parameters of the Significant Height Revisions used within this page heading, these parameters are:

The term Significant Height Revisions applies to any listed hill whose interpolated height and Ordnance Survey or Harvey map summit spot height has a 2m or more discrepancy when compared to the survey result produced by the Trimble GeoXH 6000 or analysis of data produced via LIDAR, also included are hills whose summit map data is missing an uppermost ring contour when compared to the data produced by the Trimble or by LIDAR analysis.

Therefore, the new listed summit height of this hill is 430.1m and this was derived from LIDAR analysis, this is 4.1m higher than its previously listed height of c 426m which was based on interpolation of 5m contouring that appeared on the OS Maps website. 

 

The full details for the hill are:

Group:  Axe Edge

Name:  Dow Low

OS 1:50,000 map:  119

Summit Height (New Height):  430.1m (LIDAR)

Summit Grid Reference:  SK 09419 68071 (LIDAR)

Col Height:  396.3m (LIDAR)

Col Grid Reference:  SK 09251 68164 (LIDAR)

Drop:  33.8m (LIDAR)

 

Myrddyn Phillips and Aled Williams (October 2022)

 

 

 

 

Mapping Mountains – Hill Reclassifications – The Fours – The 400m Hills of England

 

Dow Low (SK 094 680) – 400m Sub-Four reclassified to Four

There has been a reclassification 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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Dow Low (SN 094 680)

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 listing of The Fours are three categories of sub hills, with this hill reclassified from 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 2^nd edition of the booklet containing this list was published by Mapping Mountains Publications on the 24^th April 2018.

The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams

The name the hill is listed by is Dow Low, and it is adjoined to the Axe Edge group of hills, which are situated in The Southern Pennines (Region 36), and it is positioned with the B5053 road to its west and the A515 road to its north-east, and has the town of Buxton towards the north-west.

Extract from the Ordnance Survey 1:25,000 Explorer map

When the 2^nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018, this hill was included as a 400m Sub-Four and listed with an estimated c 29m of drop, based on an estimated c 426m summit height and an estimated c 397m col height, with both heights based on interpolation of 5m contouring that appeared on the OS Maps website. 

Extract from the OS Maps website

The hill is also shown in this extract from the WalkLakes website

The prominence of this hill has been created from the quarrying activities of the Hindlow Quarry.  When it was included as a 400m Sub-Four, imagery on Google Maps and Google Earth was examined with the conclusion that the hill is solid and stable.

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.

Therefore, the reclassification of this hill from 400m Sub-Four status is due to LIDAR analysis, resulting in a 430.1m summit height and a 396.3m col height, with these values giving this hill 33.8m of drop, which is sufficient for it to be classified as a Four.

 

The full details for the hill are:

Group:  Axe Edge

Name:  Dow Low

OS 1:50,000 map:  119

Summit Height:  430.1m (LIDAR)

Summit Grid Reference:  SK 09419 68071 (LIDAR)

Col Height:  396.3m (LIDAR)

Col Grid Reference:  SK 09251 68164 (LIDAR)

Drop:  33.8m (LIDAR)

 

For the additions, deletions and reclassifications to The Fours – The 400m Hills of England reported on Mapping Mountains since the December 2013 publication of the 1^st edition of this list by Europeaklist please consult the following Change Registers:

 

The Fours

 

The Fours – 400m Sub-Four

 

The Fours – 390m Sub-Four

 

The Fours – 390m Double Sub-Four

 

Myrddyn Phillips and Aled Williams (September 2022)

 

 

Mapping Mountains – Hill Reclassifications – The Fours

THIS HILL HAS SUBSEQUENTLY BEEN RECLASSIFIED TO FOUR STATUS

Dow Low (SK 094 680) – 400m Sub-Four addition

There has been an addition to the listing of The Fours due to analysis of data on the OS Maps website, which is the recent replacement for OS Get-a-map.  The Fours is the title for the list of 400m hills of England and takes in all English hills at or above 400m and below 500m in height that have a minimum 30m of drop, the list is co-authored by Myrddyn Phillips and Aled Williams and the 2^nd edition of the booklet containing this list was published by Mapping Mountains Publications on the 24^th April 2018.

Accompanying the main list of The Fours are three categories of sub hills, with this hill being added to the 400m Sub-Fours.  The criteria for 400m Sub-Four status are all English hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop. 

 

Prior to analysis of data on OS Maps this hill was not classified as its present construction is the result of mining activity from the Hindlow Quarry; therefore it does not possess any upper ring contours on the Ordnance Survey 1:50,000 Landranger or 1:25,000 Explorer maps.

Extract from the Ordnance Survey 1:25,000 Explorer map

The land where the summit of the hill is situated is positioned on that associated with Dow Low (SK 093 675) and therefore it is listed by the same name.  The hill is situated in the Southern Pennines and is placed in Region 36, with its Cardinal Hill being Axe Edge (SK 035 706).  The hill is positioned between the B 5053 road which is to its west and the A 515 road to its north-east and has the town of Buxton to its north-west.

View of Dow Low (SK 094 680)

As the summit of the hill is not a part of designated open access land and a part of a working quarry permission to visit should be sought, for those wishing to do so an ascent from the north-east may prove the easiest.

The addition of this hill to 400m Sub-Four status is due to the analysis of data on the OS Maps website coupled with analysis of imagery on Google Maps and Google Earth with the conclusion that the hill is solid and stable.  The mapping on the OS Maps website gives contour intervals at 5m which has enabled the height of the summit and col to be estimated when compared to the lack of detail on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps.  Therefore with an estimated summit height of c 426m based on an uppermost 425m ring contour on OS Maps and an estimated col height of c 397m, based on col contouring on OS Maps between 395m – 400m, this hill is now listed with c 29m of drop, which is sufficient for it to be classified as a 400m Sub-Four.

Extract from OS Maps

The full details for the hill are:

Cardinal Hill:  Axe Edge

Summit Height:  c 426m

Name:  Dow Low

OS 1:50,000 map:  119

Summit Grid Reference:  SK 094 680

Drop:  c 29m

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:

The Fours

The Fours – 400m Sub-Four

The Fours – 390m Sub-Four

The Fours – 390m Double Sub-Four

Myrddyn Phillips and Aled Williams (August 2018)