Savouring Minehead's Landscape
1st - 5th May 2009
|WHERE ? OUR WALKS MAP HEIGHTS FIGURES TRACKS FINAL READ ME|
Our walks, ably led by Helen (R), John (E) and also by Yours truly, took us through the varied landscape that characterizes this picturesque part of the Exmoor National Park, straddling Somerset and Devonshire. The rugged coast line between Lynmouth and Minehead and the hillier inland paths reaching the historic villages of Dunster, Porlock and the highest point in Somerset, namely Dunkery Beacon (519 m), all echoed to the sound of our eager footsteps!
All this, excellent weather and good walking conditions underfoot made for an unforgettable CLOG away break.
Now prepare ye for some plots and graphs. Not too overwhelming, but hopefully quite interesting! You will see here:
How far from London? Our residence in Minehead was about 106 miles from the centre of London and close to due west therefrom. The centre of London is officially taken as the intersection of The Strand, Whitehall and Cockspur Street. This intersection is often referred to as Charing Cross, not to be confused with the nearby Victorian Eleanor Cross itself, nor the station in front of which the cross stands. The detailed figures, for the fun of it, are as shown below.
Waxing a tad technical. Our "straight line" distances are actually "great circle" distances on the earth's surface. In this case, we assume the earth to be spherical, which is not far off the mark. I mean, the shape of our Planet Earth - bumps, warts and all - is called a Geoid. However, the Geoid is far too "bumpy" a candidate for a universal system to be used by a GPS. So GPSs, and Sat Navs in general, use the WGS84 system, which assumes that the earth has the nice smooth regular shape of an ellipsoid; this shape is derived from the mean sea levels (more than one!) found on our Planet Earth. For rough and ready estimates of distance, a further simplification can be made by assuming that the earth has the shape of a sphere as opposed to an ellipsoid, and this simplification can give us a maximum error of about 0.1% in the distance values compared to those given by our GPS. Not that much really! Can't complain! Indeed, we can speak of the distances as the "hypothetical crow" (cornix hypothetica) flies.
The map of the West Somerset Railway shows us how Minehead relates to the local area, especially to the East, the Quantocks and Taunton. The train journey from Minehead to Bishops Lydeard is about 20 miles, making the West Somerset Railway one of the longer preserved lines in Britain.
We got some respectable, yet leisurely, miles under our feet and managed to soak up a good proportion of the landscape that this corner of Somerset has to offer. Indeed, we accomplished our walks without undue reliance on transport - straight from our doorstep, so to speak.
Just a short note here, for the record, as it were. On our May 03 walk, two of us first went up to Lynton before starting our actual coastal walk from Lynmouth. This, and our visit to Lynmouth Church, may have added about two miles to the nominal value of 13 miles.
The starting point for three of our walks was on our doorstep. Minehead was small enough to allow us to reach the countryside very easily and quickly.
Map Distortion. Because we don't live on a flat earth - unless you are a convinced "flat-earther" - maps are inevitably a distortion of what is. In other words, it's all a matter of mapping a curvaceous surface onto a flat surface. We don't want to carry curvaceous representations of the terrain on our walks, do we? In our case, the northern length of our map grid is stretched out by something like an extra 0.18 %, to make it the same on the page as the length of the southern part of our map grid. Not that much for hiking purposes really! Can't complain!
Grid Scales. We were west of the Greenwich meridian; hence the negative longitude values. The map grid scales translate to 1.112 Km per 0.01° latitude and a mean of 0.694 Km per 0.01° longitude (WGS standard), both when using 6371.0 Km as the volumetric mean radius of the earth. It is interesting to compare the present longitude distance-to-degree ratio with that for other walks. It you do this, you will see that the further north you go, the less Km per degree longitude you get. Once you get to the Lake District the reduction in this ratio compared to that for walks in the south is quite noticeable. In Scales, in the Lake District, we already have a slightly smaller value of 0.644 Km per 0.01° longitude - a difference of 50 metres per 0.01° longitude compared with our Minehead walks.
We reached our highest point at 519 m above mean sea level on Dunkery Beacon - as per our "Facts and Figures" just below, where the discrepancy between 519 and 513 m is also broached. Of course, maximum ascent and descent figures are normally greater than the maximum height attained. Indeed, it's the total ascent which gets closer to being a measure of our fitness, rather than the maximum height reached.
The height profiles for the two coastal walks (May 3 and 5) are more "jittery" than the profiles for the other two walks (May 2 and 4) because of the "up-down" nature that can often be associated with coastal paths; this of course influences the "total ascent" and "total descent" figures as considered in the "Facts & Figures" section below.
Here are some "vital statistics" in metric and imperial units. If we look more closely at these figures, we can see that our starting heights on May 2, 4 and 5 are the same; this is of course because on the three days, we started from the same place, namely the doorstep of our residence. Similarly, the end points of our walks on May 2 and 3, at Porlock church, are the same. The height of Dunkery Beacon in the figures below is 513 m, slightly less than the official 519 m; this is likely to be due to (1) my path drawing and (2) possible inaccuracies in the otherwise very good web-based mapping tools that I use.
What about total ascent and descent? The coastal path (May 3), has noticeably greater total ascent and descent than when scaling Dunkery Beacon (May 2). Even so, for three walks (May 2, 3 and 5), our total ascent and descent figures all have an order of magnitude of about one kilometre! In other words, it is not just a question of how far we walked, but also of the amount of climbing and descending we had to do. In other word, for example, 20 miles on the flat can be less strenuous than 10 miles in hilly country, something which fell walkers are well aware of!
It may be worth mentioning that the total length our walk is measured on the surface of the WSG84 spheroid. However, we can consider this, without undue loss of accuracy, as being on a conceptual "flat" plane at mean sea level, using the OS sea level reference as explained on OS "hiking" maps. There you are!
If you are keen to see our walks superimposed on an Ordnance Survey® (OS) map or on another system such as Google Maps®, then you can use the following files for May 2, 3, 4 and 5 respectively, to do so. The data are based on WGS84. Of course, for copyright reasons, I do not show the OS-based or Google-based maps here.
Any map is an approximate representation of what is. Practicality and scale are relevant considerations. We are not dealing with a planning application calling for detailed spatial descriptions of intricate boundaries. For us in the hiking community, the degrees of accuracy and precision should be just enough to give us useable and helpful knowledge of the terrain about us and beneath our feet. I hope my humble endeavours on this page are in this respect interesting for, and useful to, you my reader!