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

 

Knott (NY 714 012) – Four reclassified to 400m Sub-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 prompted by Joe Nuttall who produced a summit analysis programme using LIDAR.  These details are being evaluated by a number of people, including Ronnie Bowron who passed the details of this hill to us.  LIDAR analysis was then conducted by Aled Williams and subsequently by Myrddyn Phillips. 

LIDAR image of Knott (NY 714 012)

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 being reclassified 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 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 Knott, and it is adjoined to The Calf group of hills, which are situated in the Howgill Fells (Region 35, Section 35A: The Northern Pennines), and it is positioned with a minor road to its south-east, the A685 road to its north and the A683 road to its east, and has the village of Ravenstonedale towards the north north-east.

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 Four and listed with an estimated c 31m of drop, based on the 1,522.8ft (464.2m) surface height on the Ordnance Survey series of Six-Inch maps and an estimated c 433m col height based on a comparison between Ordnance Survey 1:25,000 Explorer map and Harvey 1:25,000 Superwalker map col contours, with details in the accompanying Notes section stating; Four status assigned via comparison of OS and Harvey map col contours, with the former between 430m – 440m and the latter between 420m – 435m indicating that the col is between 430m – 435m, with an estimated height of c 433m and a drop of c 31m. 

Extract from the Ordnance Survey series of Six-Inch maps

Extract from the Harvey 1:25,000 Superwalker map

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 to 400m Sub-Four status is due to LIDAR analysis, resulting in a 465.8m summit height and a 437.1m col height, with these values giving this hill 28.7m of drop, which is insufficient for it to be classified as a Four.

 

The full details for the hill are:

Group:  The Calf

Name:  Knott

OS 1:50,000 map:  91

Summit Height:  465.8m (LIDAR)

Summit Grid Reference:  NY 71422 01291 (LIDAR)

Col Height:  437.1m (LIDAR)

Col Grid Reference:  NY 70987 01254 (LIDAR)

Drop:  28.7m (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

 

Our thanks to Ronnie Bowron for passing on the details of this hill to us

Aled Williams and Myrddyn Phillips (March 2022)

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

Knott (SD 676 940) – 400m Sub-Four deletion

There has been a deletion 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 initially conducted by Aled Williams and subsequently by Myrddyn Phillips. 

LIDAR image of Knott (SD 676 940)

The criteria for the list that this deletion 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 deleted 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 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 Knott and it is adjoined to the The Calf group of hills, which are situated in the Howgill Fells in the Yorkshire Dales, and it is positioned with the A683 road to its south-east and the A684 road to its south-west, and has the town of Sedbergh towards the south-west.

Prior to LIDAR analysis this hill was listed with an estimated c 20m of drop, based on a 429m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 409m col height, based on interpolation of contouring between 400m - 410m, and latterly between 405m - 410m that appeared on the interactive mapping on the OS Maps website.

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

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 deletion of this hill from 400m Sub-Four status is due to LIDAR analysis, resulting in a 429.7m summit height and a 410.0m col height, with these values giving this hill 19.7m of drop, which is insufficient for it to be classified as a 400m Sub-Four.

The full details for the hill are:

Group:  The Calf

Name:  Knott

OS 1:50,000 map:  98

Summit Height:  429.7m (LIDAR)

Summit Grid Reference:  SD 67644 94087 (LIDAR)

Col Height:  410.0m (LIDAR)

Col Grid Reference:  SD 67446 94201 (LIDAR)

Drop:  19.7m (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 (May 2018)

English Hill Lists - Major Differences between The Fours and the Tumps

The following are the major differences between the listings of The Fours and the Tumps at the time of compilation / publication of The Fours by Europeaklist.

Upon accurate Trimble surveying and reviewing of data both listings will no doubt undergo amendments.

Cardinal Hill:  The Cheviot

486m    Dryhope Hill    80    NT 928 116    29m

Sub-Four with P29 / Tump with P31

The Tumps list has 31m of drop based on a col height of 455m.  Geograph has a 457m spot height on the area of the col at NT 931 118, giving this hill 29m of drop.

The Fours Europeaklist booklet page 8.

Cardinal Hill:  Scafell Pike

463m    Brown Rigg    90    NY 305 146    c 27

Sub-Four with P27 / Tump with P31

The Tumps list has 31m of drop based on Ordnance Survey col contouring (430m – 440m).  The Fours lists the hill with c 27m of drop based on a combination of Ordnance Survey and Harvey Maps (435m – 450m) col contouring.  If taking in to account Harvey Maps information the col is between 435m – 440m with an estimated col height of c 436m, giving c 27m of drop.

The Fours Europeaklist booklet page 11, Note number 29 (page 28).

Cardinal Hill:  Burnhope Seat

426m    Catterick    92    NY 994 359    29m

Sub-Four with P29 / Tump with P30

The Tumps list has this hill as Catterick Moss with 30m of drop.  This hill has an extensive comment in the notes section of The Fours concerning the drop value.  The trig pillar’s flush bracket height, photos of the summit area, levelled heights on the summit from Ordnance Survey 1:2,500 maps, levelled heights on the col area from Ordnance Survey 1:2,500 maps and a repeated drive over the col in a Google car were all taken in to account when deciding upon the listed drop of 29m.

The Fours Europeaklist booklet page 15, Note number 85 (page 30).

Cardinal Hill:  The Calf

464m    Knott    91    NY 714 012    c 31

Four with P31 / Not listed as a Tump

The TumpPs list does not include this hill.  The Fours lists the hill with c 31m of drop based on a combination of Ordnance Survey (430m – 440m) and Harvey Maps (420m – 435m) col contouring.  If taking in to account Harvey Maps information the col is between 430m – 435m with an estimated col height of c 433m, giving c 31m of drop.

The Fours Europeaklist booklet page 15, Note number 97 (page 31).

Cardinal Hill:  Pen-y-ghent

411m    Pt. 411m    98    SD 953 648    c 29

Sub-Four with P29 / TumpP with P30

The Tumps list has this hill as Malham Moor with a drop of 30m based on a col height of 381m.  The Fours lists the hill with an estimated c 29m of drop based on a col height of c 382m.

The Fours Europeaklist booklet page 17, Note number 123 (page 31).

Cardinal Hill:  Ward’s Stone

c 430    Bowland Knotts    98    SD 727 606    c 86

Four with P86 / Tump listed to different summit

This is a summit re-location from the previously listed top at SD 722 603.  The listed summit at SD 727 606 has a small c 430m ring contour whilst the previously listed top at SD 722 603 has a 430m triangulation pillar with a flush bracket height of 429.932m.  Even though ground a few metres from the trig pillar is slightly higher than the base of the trig, best available evidence points toward the summit at SD 727 606 being slightly higher.  Definitely needs a Trimble survey.

The Fours Europeaklist booklet page 18, Note number 130 (page 32).

Cardinal Hill:  Axe Edge 

407m    Pt. 407m    119    SK 054 680    c 29

Sub-Four with P29 / Tump with P31

The Tumps lists this hill as Brand End with a drop of 31m, giving the height of the col as 376m.  The listing of The Fours estimates the height of the col as c 378m with col contouring between c 375m – c 380m.

The Fours Europeaklist booklet page 21.

Cardinal Hill:  Axe Edge

436m    Upper Edge    119    SK 076 684    20m

Sub-Four with P20 / Tump with P30

The Tumps list has 30m of drop based on a col height of 406m.  The drop in the list of The Fours is 20m based on a 416m spot height on the area of the col on Geograph.  The land that extends from the col has been extensively quarried.

The Fours Europeaklist booklet page 21, Note number 226 (page 35).

Cardinal Hill:  Cilfaesty

403m    Caer Caradoc    137, 148    SO 309 757    56m

Four with P56 / 399m Tump with P52

The 403m spot height is based on the 1,321.4ft (402.76m) levelled height on the Ordnance Survey (OS) 1:2,500 map.  This matches the rounded up 403m height on the old OS 1:50,000 map.  This height is taken to the earthen ramparts of an ancient Iron Age Hill Fort.  Whereas the 399m Tump height is the spot height on current OS 1:50,000 and 1:25,000 maps and is taken to the lower central part of the ancient structure.  The exclusion from the 4 category of the Tumps on the Hill Bagging website may be due to not recognising ancient structures from antiquity that are permanent in nature as being included in the height of a hill, whereas The Fours view such structures as being permanent and a part of the hill.  

The Fours Europeaklist booklet page 24, Note number 272 (page 37).

Cardinal Hill:  High Willhays

454m    South Hessary Tor    191    SX 597 723    c 35

Four with P35 / Tump listed to lower summit

This is a summit re-location from the previously listed top at SX 594 730 as Harvey Maps has a 454m summit spot height as opposed to the previously listed summit (named Middle Hill on Harvey Maps) which has a 451m spot height.

The Fours Europeaklist booklet page 26, Note number 291 (page 37).

‘The Fours’ is available as an e-booklet version and a print-booklet version with or without accompanying photographs on the Europeaklist website.

 https://sites.google.com/site/europeaklist/Home/united-kingdom/england/the-fours  

'The Fours' is also available for GPS Waypoints, Google mapping and on-line hill bagging tick lists on the Haroldstreet website.

The Fours:  http://www.haroldstreet.org.uk/waypoints/download/400s/?list=fours

Sub-Fours:  http://www.haroldstreet.org.uk/waypoints/download/400s/?list=subfours

Double Sub-Fours:  http://www.haroldstreet.org.uk/waypoints/download/400s/?list=double-subfours