The Fours - The 400m Hills of England
Transitional list with P15 subs
Introduction
The 400m hills of England take in a variety of upland landscape, including what can be considered as mountain, moor, heath, grassland and high pasture. These hills take in the majority of upland areas the country has to offer and visiting them will take you on a journey the length and breadth of England.
This listing is the most comprehensive and accurate to this height band of hills ever published.
The List: The listing of the The Fours - The 400m Hills of England takes in all English hills at or above 400m and below 500m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Fours, with the criteria for this sub category being all English hills at or above 400m and below 500m in height with 15m or more and below 30m of drop.
Publication History: The initial compilation of this list was completed in November 2002 and entitled The 400m Peaks of England and was first published on 19th December 2002 on the RHB Yahoo Group file database along with the equivalent Welsh and Manx hills, with the file entitled the 400m hills of England, Isle of Man and Wales, this file was uploaded by Rob Woodall who later augmented data from E D ‘Clem’ Clements into the database.
It was the publication on the RHB Yahoo Group file database that was later duplicated en masse by Mark Jackson without consultation with the author, with these data forming the equivalent part of the Tumps. This has resulted in years of undue data divergence that is ongoing.
The next publication of this list was initiated by Mark Trengove who expressed interest for Europeaklist to publish it. This enabled the list to be fully re-evaluated and leading up to this publication selected updates to the list were posted on the RHB Yahoo Group forum.
The subsequent Europeaklist publication on the 15th December 2013 was entitled The Fours and led the way to the list becoming co-authored with Aled Williams. The listing of The Fours was later published on the 6th January 2014 by Phil Newby on his Haroldstreet website, and all future updates to the list have been catalogued on the Mapping Mountains site.
The list was fully re-assessed for its next publication on the 24th April 2018 by Mapping Mountains Publications and on the Haroldstreet website with its title now established as The Fours – The 400m Hills of England.
Maintaining the List: The above publications relied upon a hand written master list, which was used for many years with all necessary updates and additional information being added. The list is now maintained in spreadsheet format, with all necessary information appearing in the Mapping Mountains publication. Between the first publication of this list and its latest publication on Mapping Mountains it has undergone a number of significant updates and the timeframe for these are given below.
Significant Updates:
2002: The original list did not use interpolation for estimated heights and therefore accepted Ordnance Survey spot heights as fact. With the accompanying Hills to Measure sub list only including P20 hills that once surveyed stood a chance of entering the main P30 list.
2012: The original list relied upon paper mapping with the newly published Ordnance Survey 1:25,000 Explorer maps prioritised over the 1:50,000 Landranger maps. The advent of online mapping included the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. This mapping had many spot heights not on other publicly available Ordnance Survey maps and enabled a full review of all data in this list.
The subsequent re-evaluation of this list which included drop values, interpolated heights and the accompanying sub list standardised to P20 relied heavily upon the Interactive Coverage Map hosted on the Geograph website. During the updating of this list English 400m hills were listed down to P14 for full capture of P20 subs. These details now form the basis of this transitional listing which for the first time uses P15 subs accompanying the main P30 list.
2013: Numerical accuracy within hill lists has dramatically increased compared to when Ordnance Survey paper mapping was the tool of reference. This increased accuracy is due to the advent of independent surveyors using survey grade GNSS receivers and for this list it is the use of the Trimble GeoXH 6000 that has greatly benefited the numerical data, with the first 400m English hill surveyed with this equipment in January 2014 and with these surveys ongoing to the present day.
2016: The use of the LIDAR (Light Detection & Ranging) technique has revolutionised hill listings resulting in a plethora of reclassifications. Our use of LIDAR started in November 2016 and is ongoing, with this list heavily dependent upon the accuracy produced from LIDAR analysis.
2022: The Mapping Mountains publication of The Fours - The 400m Hills of England commences on the 1oth September.
Major Advances: The list has changed greatly since its first publication, with the advent of independent surveyors and the use of LIDAR enabling greater numerical accuracy.
Place name research within hill lists has also made dramatic progress since the first publication of this list, with local enquiry and historical research enabling greater depth and understanding for the hill names used.
Since the advent of Mapping Mountains in November 2013 all status changes to this list are documented in Hill Reclassification posts on this site, with comprehensive Change Registers giving historical context to status changes that have occurred, and with all major significant amendments also documented.
Mapping Mountains Publication: For the Mapping Mountains publication of the The Fours - The 400m Hills of England the list has been fully re-evaluated using highly accurate numerical data produced from the LIDAR technique and all available results from the use of GNSS receivers such as with the Trimble GeoXH 6000 and Leica surveys. Each hill name has been considered for its most appropriate use with Ordnance Survey historical and contemporary mapping used in conjunction with any local enquiry.
The accompanying sub list entitled the *Sub-Fours is now listed down to P15 and an explanation for doing this appears toward the end of this introductory article. The end result is the most accurate and comprehensive listing to this height band of hills ever produced.
The Fours –The 400m Hills of England downloadable list in Google Doc format
The Mapping Mountains list consists of the following:
Name: This is considered the most appropriate name for the hill, based on local usage where this is known. The name used does not always correspond to contemporary Ordnance Survey map spelling and/or composition or the name may not appear on any Ordnance Survey map. Where an appropriate name is not forthcoming for the hill, the Point (for example; Pt. 465.1m) notation is used rather than making up a name that has no local or historical evidence of use.
Summit Height (m): This gives the height in metres of the hill above Ordnance Datum Newlyn (ODN), often referred to as sea level. Where a height is quoted to a decimal place it implies that the hill has been surveyed by GNSS receiver (survey grade GPS) or obtained from LIDAR analysis (these heights may not match current Ordnance Survey map heights), with the heights produced by GNSS receiver converted to OSGM15.
1:50,000 Map: This column gives the number or numbers of the 1:50,000 Ordnance Survey Landranger map that the summit of the hill appears on.
1:25,000 Map: This column gives the number or numbers of the 1:25,000 Ordnance Survey Explorer map that the summit of the hill appears on.
Summit Grid Reference: This is the ten figure grid reference for the summit of the hill. This has either been produced by an accurate survey via GNSS receiver or from LIDAR analysis.
Summit Grid Reference extracted from: Details of where the ten figure grid reference for the summit was derived.
Drop (m): This column details the prominence of the hill, otherwise known as drop or re-ascent. The drop is the height difference between the summit and the lowest connecting col to the higher parent peak along the watershed.
Col Grid Reference: This is the ten figure grid reference for the col of the hill. This has either been produced by an accurate survey via GNSS receiver or from LIDAR analysis.
Col Grid Reference extracted from: Details of where the ten figure grid reference for the col was derived.
Col Height (m): This gives the height in metres of the col of the hill above Ordnance Datum Newlyn (ODN), often referred to as sea level. Where a height is quoted to a decimal place it implies that the col has been surveyed by GNSS receiver (survey grade GPS) or obtained from LIDAR analysis (these heights may not match current Ordnance Survey map heights), with the heights produced by GNSS receiver converted to OSGM15.
Notes: This column gives additional information relating to the hill, including headings for Place Name Information, Numerical Data and Listing History, with the latter relating to prominence based hill lists.
*Sub-Fours: For many years the standard sub-list accompanying a P30 main list used 20m minimum drop. The initial reason for including a sub list was to capture those additional hills that may upon re-assessment via map study be included in the main P30 listing. The advent of independent surveyors and LIDAR analysis has granted exceptional numerical accuracy, resulting in many, if not all originally sub listed marginal hills now having their numerical data and hence their status determined. This brings in to question the continued use of a sub list.
However, if hills whose status is now accurately determined were excluded from a sub list the uninitiated newcomer may query their exclusion. Because of this it is easier to include all sub listed hills, even if their status has been accurately determined. Outside of helping the uninitiated newcomer with documenting accurate heights and drops the initial purpose of a sub list is now redundant.
Because of this the continued use of a sub list has taken on a different role.
Prior to this Mapping Mountains publication of The Fours – The 400m Hills of England, this list included three accompanying sub lists:
400m Sub-Fours – English hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop.
390m Sub-Fours – English hills at or above 390m and below 400m in height that have 30m minimum drop.
Double Sub-Fours – English hills at or above 390m and below 400m in height that have 20m or more and below 30m of drop.
As the hills in the two 390m sub lists are included in other lists and are outside of the 400m height band that this listing portrays, we are now excluding these sub lists from the transitional list of The Fours – The 400m Hills of England.
As the primary role of including a sub list has altered from its initial conception and although the continued inclusion of marginal hills whose numerical accuracy and status has been determined benefits the uninitiated newcomer, the primary role of a sub list is now one that is an extension of the main list. Simply put a sub list is now an excuse for listing more hills under the specified height band and by doing so giving a more comprehensive list of hills.
As our height band is to 400m and as the main list uses a minimum of 30m of drop, within this transitional list we are listing our accompanying sub hills using a minimum of 15m of drop.
The use of P15 for our accompanying sub list results in a greater and more comprehensive listing to the 400m hills of England.
Therefore, this transitional list of The Fours – The 400m Hills of England comprises the following:
The Fours – English hills at or above 400m and below 500m in height that have 30m minimum drop.
Sub-Fours – English hills at or above 400m and below 500m in height that have 15m or more and below 30m of drop.
This list and its use of P15 for our Sub-Fours are transitionary as each grouping of hills will be published when full LIDAR coverage is available. Until the list is published in its entirety Mapping Mountains will catalogue changes based on the pre-transitional list.
Myrddyn Phillips and Aled Williams (September 2022)
Access: This is a collection of English hills that meet set criteria and although such a list can be a reference for people to visit them, for those wishing to do so they should abide by any legal restriction and if unsure of permissible access ask permission to visit from the respective landowner.
Risks: Hill walking is an activity with risks and dangers, both natural and man-made. You should not attempt hills beyond your capabilities, and should fully appraise yourself of, and prepare for, the possible risks before attempting to visit any hill. Participants in these activities should be aware of and accept these risks, and be responsible for their own actions and involvement.
Thanks: With special thanks to Mark Trengove for continued support and advice over many years, Rob Woodall who inputted data for the list published on the RHB Yahoo Group file database and Phil Newby for Harodstreet publication of this list.
This list will appear in instalments when Groups of hills are ready to publish. This is dependent upon the availability of full LIDAR coverage; therefore Groups may not appear in numerical order.
When fully appraised Groups of hills will be published at 7.00pm on the 10th and/or the 20th of each month.
The fifteenth instalment is to the Grayrigg Forest group of hills.
The sixteenth instalment to the Tarn Crag group of hills will be published on the 20th April 2023.
The Fours –The 400m Hills of England downloadable list in Google Doc format
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