1000m Twmpau

1000m Twmpau

Introduction

To access the 1000m Twmpau list please click {here}

Yr Wyddfa - the highest mountain in Wales

The concept of the Twmpau:

The first published lists to the P30 hills under the 500m height band were made available on Geoff Crowder’s v-g.me website in 2002 and 2003.  These hills appeared in five separate lists and were split into 100m height bands.  As their titles imply the listings are to Welsh hills; they are:

The Welsh 400 Metre Peaks

The Welsh 300 Metre Peaks

The Welsh 200 Metre Peaks

The Welsh 100 Metre Peaks

The Welsh 30-99 Metre Peaks

These listings were envisaged as part of an accumulated list taking in eleven separate height bands.  The remaining six lists are to the 100m height bands above 500m with the final list being to the Welsh 1000m P30 hills.  Although these lists were prepared for publication, they were never submitted as their respective hills had already been published in the combined lists of the Deweys and Hewitts, which were available on Geoff’s v-g.me website.

The advent of the Mapping Mountains site now enables my original concept to be fulfilled and publish the six remaining lists.

The accumulated list taking in all eleven 100m height band lists and therefore all the Welsh P30s has now been named Twmpau.  The Welsh word twmpath is translated as hillock, which is an apt description for many of the hills in the combined list, and has been used as twmp in certain parts of Wales, with the literal translation of the word being tump.  Although the Welsh word twmp forms part of the name of this list, the name Twmpau is an acronym standing for thirty welsh metre prominences and upward.  This title also pays due deference toward the name and acronym coined by Gary Honey and Jon Foote for the list by Mark Jackson that was made available on the Yahoo Group RHB file database in 2009, which relied upon much of its data for Welsh hills from the lists published on Geoff Crowder’s v-g.me website and the RHB file database.

Brief History:

Many Welsh hill lists evolve from their previous counterparts and the Twmpau is no different as the use of 30m for a minimum drop value, or its whole numbered imperial equivalent of 100ft can be traced back to 1925 when Carr and Lister used 100ft of drop in their list to The Mountains of Snowdonia.  It would be another 59 years before Terry Marsh used the metric whole numbered equivalent of 30m as a drop value in The Summits of Snowdonia.  Others have followed, some of note are Tony Blackburn (1985, The 500 Metre Tops of England and Wales), Kevin Borman (1990, The Mountains of Wales), Alan Dawson (1992, The Absolute Summits of England and Wales [Sweats] later to become; 1997, The Welsh Hewitts) and Michael Dewey (1995, The 500-Metre Tops of England and Wales).

The above P30 listings were expanded downwards in absolute height by ‘Clem’ Clements and Myrddyn Phillips, who worked independent of one another.  Clem listed down to 100m in absolute height and included sub hills down to P27m, whilst Myrddyn listed down to 30m in absolute height and included sub hills down to P20m.  The first of these independently compiled lists to be published were the lists compiled by Myrddyn Phillips, appearing on Geoff Crowder’s v-g.me website, with the 400m P30 list also appearing on the RHB file database.  This was eventually followed by the uploading of the lists compiled by ‘Clem’ Clements’ on the file database of the RHB Yahoo Group.  It was these two lists that formed the basis for the majority of Welsh Tumps listed by Mark Jackson in 2009.

Much of this data related to hills that were unnamed on contemporary Ordnance Survey maps and were in fact, listed by names invented by the hill list author.  Unfortunately, many of these invented names have been duplicated and are now found in the current listing of the Tumps.  The names of hills listed in the Twmpau will not rely upon invented names that have no local or historical evidence of use and the author will endeavour to use the most appropriate composition for each hill name.

In summary, the first published lists using 100ft / 30m of drop appear below, all except for the Carr and Lister publication use height bands that are within the Twmpau.  These lists were compiled by:

1925    Carr and Lister    The Mountains of Snowdonia.  2,000ft minimum height with 100ft minimum drop.

1984    Terry Marsh    The Summits of Snowdonia.  600m minimum height with 30m minimum drop.

1985    Terry Marsh    The Mountains of Wales.  600m minimum height with 30m minimum drop.

1995    Michael Dewey    Mountain tables    The 500-Metre Tops of England and Wales.  500m minimum height with 30m minimum drop.

2002    Myrddyn Phillips    The Welsh 400 Metre Peaks.  400m minimum height with 30m minimum drop.

2003    Myrddyn Phillips    The Welsh 300 Metre Peaks.  300m minimum height with 30m minimum drop.

2003    Myrddyn Phillips    The Welsh 200 Metre Peaks.  200m minimum height with 30m minimum drop.

2003    Myrddyn Phillips    The Welsh 100 Metre Peaks.  100m minimum height with 30m minimum drop.

2003    Myrddyn Phillips    The Welsh 30-99 Metre Peaks.  30m minimum height with 30m minimum drop.

The list of the 1000m Twmpau includes all Welsh hills that are 1000m and above and below 1100m in height, with 30m minimum drop.

Any accompanying Sub-List includes all Welsh hills that have 20m and more and below 30m of drop.

To access the 1000m Twmpau list please click {here}

For many years Glyder Fawr appeared on Ordnance Survey maps as 999m in height.  A survey conducted by John Barnard, Graham Jackson and Myrddyn Phillips elevated its known height to 1000.8m, with the new rounded up figure of 1001m now appearing on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map

The list consists of the following:

Group:  Each hill is listed by the hill group that it is a part of.  Each Group follows topography and were determined by Aled Williams and Myrddyn Phillips.  The name of each Group appears under the highest hill in its topographical area.

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 bwlch to the higher parent peak along the watershed.

Bwlch Grid Reference:  This is the ten figure grid reference for the bwlch of the hill.  This has either been produced by an accurate survey via GNSS receiver or from LIDAR analysis.

Bwlch Grid Reference extracted from:  Details of where the ten figure grid reference for the bwlch was derived.

Bwlch Height (m):  This gives the height in metres of the bwlch 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 bwlch 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.

Access:  The hills in the combined lists that form the Twmpau all meet set criteria.  Although such a list can be used as a reference for people to visit the hills, please abide by any legal restriction and if unsure ask permission to visit from the landowner.

Risks:  Hill walking is an activity with risks and dangers, both natural and man-made.  Please only attempt hills within your capabilities and 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:  Relating to the overall listing of the Twmpau; with special thanks to Rob Woodall who inputted data for the list published on the RHB Yahoo Group file database and to Geoff Crowder for publication on his v-g.me website.  Thanks also to Aled Williams for encouragement with this list and advise relating to individual hill names.

To access the 1000m Twmpau list please click {here}

Arennig Fawr - just one of many P30s in Wales