What do a 700-year-old inn, Robin Hood and 340 million years of earth history have to do with a waterfall in Yorkshire? Turns out, quite a bit! A visit to Hardraw Force waterfall can feel like a trip back in time. The historic Green Dragon Inn at the start of the walk to the fall dates to the Middle Ages, and preserves many of its original features. Indeed, sitting beside the roaring fire, under the wooden beams of its roof, you’d be forgiven for expecting the whole band of merry men to come waltzing in at any moment! But there’s a deeper, much older, story to be told here, and to discover it we have to leave behind the comfortable warmth of the fire, head out the back, and journey into the wilds. From here the path follows the Hardraw Beck at a distance, before joining it for the final stretch, up through an enchanting wooded gorge to the fall itself. Hardraw Force is quite the spectacle, with the water of the beck plummeting over a lip of harder rock towards a plunge pool some 30 meters below. This is the largest single drop of any permanent, above-ground waterfall in England, a feet owed to its geology. The rocks here date to the Visean stage of the early Carboniferous, around 340 million years ago. At that time, Yorkshire was a very different place. A far cry from the wet, temperate climate we enjoy (or not!) today, this land once basked in the warm sunshine of the tropics. And yet, the Earth was in the grips of an Ice Age. Don’t expect to find any woolly mammoths or sabre-toothed cats here though (that more famous glacial period came much later). This was an age long before the first mammals, and almost 100 million years before the first dinosaurs roamed the Earth. As ice sheets waxed and waned at the poles, sea levels in these tropical latitudes rose and fell. At their highest, the region sat below a warm, shallow sea, comparable to the Bahamas of today. These waters were bursting with life, and the remains of long-gone coral reefs form the layer of limestone at the top of Hardraw Force. As sea levels fell and the shoreline crept closer, more and more mud washed in from the land and soon the reefs were buried. This is the origin of the darker mudstones found at the base of the waterfall. Between the limestone and mudstones are thick layers of coarser sandstone, laid down when sea levels dropped even further and yet more sediment washed in the from the land. Vast river deltas developed, like those of the Amazon today, and great swamps flourished atop them. Lurking within these sandstone rocks is evidence of a dragon that once dwelt here. Although, to call the beast a dragon might be a bit of an exaggeration. This dragon didn’t have wings, it certainly didn’t breathe fire, and it probably didn’t even have scales. Our ‘green dragon’ was an early tetrapod, the group of animals from which all land-living vertebrates are descended, including us humans. It was more like a large salamander, heaving its bulky body through this primeval swamp, and leaving footprints in the sand as it went. These trackways, preserved forever in a block of sandstone, provide us a brief glimpse into this lost world. The story of this specimen is quite an intriguing one. It was found by schoolboy John Chapman around 1966 or 67, who was studying the waterfall and its rocks as part of his geology classes. He gifted it to his teacher, Stuart Maude, who used the specimen in his lessons for a number of years, before eventually donating it to the Natural History Museum in London, where it remains on display to this day. A replica can also be seen on display at Cliffe Castle Museum in Keighley. But what is a trace fossil? And why are they so important to our understanding of past life? When we imagine fossils it’s hard not to picture a wonderfully complete dinosaur skeleton on display in some museum gallery. It’s a nice image, but rarely is it close to the truth. Most fossils are little more than fragments of bone or shell, leaving its discoverer with an often squashed and rarely complete jigsaw to piece together. And then there are trace fossils, not the actual remains of a living thing, but rather something that it left behind through the general activities of its life. This can include coprolites (fossil poo!), eggs shells, or in this case, footprints. While body fossils can tell us what a creature looked like, trace fossils can tell us how it lived. It's quite rare for us to come across a track-maker at the end of its track, so working out exactly whodunnit is often impossible. As such, trace fossils are often given names of their own, in this case Palaeosauropus, which means ‘old lizard foot.’ While no body fossils of our green dragon have ever been found at Hardraw, we do have fossils of similarly aged early tetrapods from elsewhere in the world, from which we can draw comparisons. From them, we can deduce that our trackmaker was 50-75 cm long and likely spent most of its time on land, only returning to the water to reproduce as frogs and salamanders do today. While only footprints, this is the oldest evidence we have for a creature of this kind, one not too far removed from our own ancestor, anywhere in the UK. So, there’s the green dragon and the earth history, but what about the Robin Hood connection? Well, to the best of my knowledge the famous outlaw never encountered a dragon (citation needed), and it’s unlikely he ever visited Hardraw. The Green Dragon Inn does date back to the 13th century though, which is when most of his exploits were said to have taken place, and the 1991 film “Robin Hood: Prince of Thieves” included an infamous scene shot at the waterfall, so I guess there’s that! Author: Jake Morton References
Bird HC, Milner AC, Shillito AP and Butler RJ, 2020. A lower Carboniferous (Visean) tetrapod trackway represents the earliest record of an edopoid amphibian from the UK. Journal of the Geological Society, 177, pp. 276-282. Milner AR and Sequeira SEK, 1994. The temnospondyl amphibians from the Visean of East Kirkton, West Lothian, Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences, 84, pp. 331-361.
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