When we're in Leeds we like to go walking in the Yorkshire Dales, which is an easily-accessible and extensive area of hills and valleys in the north of England. The first picture shows one of the routes up to one of the highest points in the Dales, called Ingleborough - one of the so-called 'Three Peaks'. It isn't a real mountain-shaped 'peak', as you can see, the summit's only about 700 metres above sea level, and it's easily walkable with a good pair of shoes, but it can be quite threatening in poor weather, and you should certainly make sure you've got proper clothing to keep you warm and dry.
Visitors from other countries often comment on the lack of trees in the landscape, and such comments used to surprise me, because it was a landscape familiar to me from a very early age, and it didn't strike me as at all unusual. But later, after I'd got to know other upland areas in Europe, I started to notice the lack of trees for myself.
Perhaps the most characteristic feature - the defining feature, in fact - of the Yorkshire Dales landscape is limestone, which underlies a large part of the region. Limestone is the light-coloured rock that you can see protruding onto the surface on the left of the photo, and on the track in the foreground. It's a permeable rock - i.e it lets water through. Water runs down through cracks in the rock, and at the same time gradually dissolves the rock and widens those cracks, so that there's very little surface water, and large parts of the area are very dry, rocky and barren-looking. There are dry valleys, dry waterfalls and all sorts of other interesting geological features. The next photo is one that I took ages ago but it's still one of my favourites - and it shows that there are some trees, after all!
The third photo shows a real curiosity - and there are lots of examples like this in the area. You can see a huge block of dark rock resting on a small limestone pedestal, and the darker rock is much, much older than the limestone. So how did it get there? Was it carried by giants? Probably people used to have such theories to explain this odd phenomenon. In fact these boulders were carried by glaciers from somewhere further north during the Ice Age. When the ice melted, they settled on the limestone surface, and since then water has eroded away the upper layers of limestone, but the bits under the boulders were protected and haven't eroded to the same extent, so they remain as pedestals supporting the boulders. There are some boulders that you can rock from side to side because they aren't very secure on their limestone supports!
There's another very significant feature of the area that you can't see from the surface. Because of the continual erosion of the rock by underground water, there's a huge network of underground caves and passages, which attract cavers in large numbers. Of course caving can be quite a dangerous activity, and in the past few days one of big local news items has been about two cavers who died underground when water levels rose quickly after heavy rain. They were experienced and properly equipped, but still, they were taken by surprise. Unfortunately these accidents happen from time to time. The cave systems are like a huge sponge, and they soak up all the rainfall. I've been in some of the big caves that are open to the general public, but apart from that I prefer to stay on the surface!
It's New Year's Eve today, so on a more cheerful note, I'd like to wish you all a very Happy New Year.
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