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 first instalment is
to the The Cheviot group of hills.
The second instalment to
the Thirl Moor group of hills will be published on the 20th September.
The Fours –The 400m Hills of England downloadable list in Google Doc format
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