SIGNIFICANT SUMMITS: A LazyMap of Greater Cambria

A LazyMap of "Greater Cambria"

Ever noticed that Wales officially has a North, Mid, South, and West, but no East?

The image below is the latest incarnation of a sketch I first made when chasing down the Significant Summits of the Cambrian Mountains, i.e. of Wales.

Noting the distribution of hills with a prominence of more than 500ft [1], I wondered at their relation to each other and drew in the cols between each pair that are linked along the watershed, and then went back to the maps to find the triplepoints where the interlinking ridges met, and lazily sketched in straight lines to give just the trend of those ridges.

This left odd and disjointed pieces floating about, and so the adjoining hills across the English border were added, as far as the Severn (and the River Weaver in the north, and the lowest col between the two [2]) which appeared to be a more natural boundary to use rather then the national border. This additional area corresponds to most of what is historically known to the English as the "Welsh Marches".

A hand-typed sketch is shown below, no less basic than the original hand-drawn one. The summits, cols, and triplepoints are generally plotted to an accuracy of a square km, though some have been nudged a pixel in any direction when in danger of merging. The three summits surrounded by dotted circles indicate the location of single-summit islands -- but not the size or shape of the islands, just as the coast is omitted from the mainland.

Despite the complete lack of other data, the hills and ridges give a remarkably good account of the shape of Wales outright [3], requiring only 2-20km of surrounding land to flesh-out the `skeleton' of the hills and ridges shown. This is in marked contrast to England which lacks somewhat in the Midlands and East [4].

For a more detailed account of the Welsh Marilyns, TACit Press publishes tables for all the Marilyns and many other hills in Wales, and for that matter the rest of the British (& Irish) Isles.

[ 1: Later extended down to 150m (492 and-a-bit feet) to concur with Alan Dawson's Marilyns, as per his Relative Hills of Britain and later amendments.]
[ 2: This col also happens to be the lowest point on the watershed between Scafell Pike, the highest point in England, and Snowdon, the highest point in Wales, arguably making it ideal as the boundary between the two groups of hills.]
[ 3: See the inset on the map below, drawn at 1/10th the scale of the main map.]
[ 4: See the LazyMap of The British Lowlands.]

[IMAGE: The +150m Prominence Hills of WALES and adjoining parts of England]

Hill Prominence # name m ft 1 Snowdon 1038 3406 2 Carnedd Llewelyn 750 2461 3 Pen y Fan 671 2201 4 Aran Fawddwy 670 2198 5 Glyder Fawr 643 2110 6 Waun Fach 622 2041 7 Cadair Idris 608 1995 8 Moel Siabod 595 1952 9 Moel Hebog 585 1919 10 Y Llethr 561 1841 11 Pumlumon 524 1719 12 Arenig Fawr 479 1572 13 Tarren y Gesail 463 1519 14 Mynydd Mawr 462 1516 15 Yr Eifl 433 1421 16 Fan Brycheiniog 423 1388 17 Sugar Loaf 413 1355 18 Craig Cwm Silyn 398 1306 19 Craig y Llyn 392 1286 20 Gyrn Ddu 385 1263 21 Moelwyn Mawr 385 1263 22 Moel y Gamelin 382 1253 23 Brown Clee Hill * 375 1230 24 Great Rhos 374 1224 25 Rhinog Fawr 363 1191 26 Stiperstones * 361 1184 27 Ysgyryd Fawr 344 1129 28 Foel Cwmcerwyn 344 1129 29 Cadair Berwyn 344 1129 30 Carn Fadryn 343 1125 31 Worcestershire Beacon * 340 1115 32 Y Garn 315 1033 33 Carnedd y Filiast 315 1033 34 Maesglase 311 1020 35 Rhobell Fawr 309 1014 36 Long Mountain 305 1001 37 Pegwn Mawr 299 981 W The Wrekin * 310 1017 * = English summit

Notes to the map:

Cols belong to the numbered summit immediately adjoining unless indicated otherwise with a dash and alternate number.
"T" denotes twin peaks -- two distinct summits (a single pair, about 10km apart in this case) with the same measured height but insufficient drop between the two for them to each count individually.
"-E" designates the lowest col between Scafell Pike (the highest and most prominent summit in England), and Snowdon (superior on both counts). Snowdon's col is about 320km (200 miles) due north of Snowdon, about 20km north-east of the centre of Glasgow.
The grid on the map corresponds with the Ordnance Survey National Grid -- the silver grid denotes the OS 100km grid squares, as matched on the inset. The yellow grid thus marks out the OS's 10km grid squares.

(top) (Significant Summits) (mail)