The Stone Forest, near Shilin, is one of Yunnan’s star attractions – a world heritage site and another geopark – around 90 minutes drive from Kunming. We toyed with the idea of metro plus bus to get there but a taxi is much quicker and much less hassle and, with six of us sharing, not so expensive. This turned out to be a very good decision, with temperatures in the high 20s much of the day.
As we approached the site we could see tall pillars of limestone appearing randomly through the vegetation in places – puzzling to me as the soil, where exposed, is a deep red colour. All was revealed when we visited the huge geological museum on the site, though. The whole process started some 260 million years ago (mya) when beds of Permian limestone, many meters deep, were lifted up above sea level by tectonic movement. A limestone pavement then started to form, as began to erode the surface. At this stage it would have looked something like Malham Cove in Yorkshire.
Over the next 10 million years or so, the warm wet coastal climate eroded the pavement into teeth-like structures. Then, however, the whole area was covered by a thick layer of flood basalts (the Emeishan basalts, produced by a plume of mantle material; Xu et al., 2007) in the late Permian, baking the outside of the teeth-like structures and filling all the gaps between.
By the late Cretaceous, 65 mya, some of the basalt had, in turn, been eroded away and the limestone started to reemerge. However 50 mya a large lake formed in the area and beds of red sandstone formed on the lake bed, presumably derived from weathered basalt. This sandstone reburied the karst limestone in places, whilst around the lake it continued to be eroded. Over the last 20 million years, further uplift has exposed more and more of the limestone and water, particularly the Bajiang river and its tributaries, has eroded it into the spectacular landscape seen today.
Our taxi dropped us at the visitor centre, from where we got an electric shuttle bus to the entrance. Nothing could have prepared us for the crowds and especially the noise – half a dozen different tour guides with loudspeakers all hectoring their groups at the same time and all the people in those groups ignoring the guides and talking loudly to their friends. Several roadside stalls did their bit for the decibel levels with loud, piped muzak. This is what it’s like on a supposedly quieter week day!
We headed for the so called Minor stone forest first, but the noise and crowds made us all feel rather claustrophobic so, spectacular as the rocks are, we took the first opportunity to head off the beaten track a little, though an area of cafes and shops.
The rocks were less dramatic here but it was quiet, apart from a cuckoo laughing at us and a man hoeing a rocky-looking field by hand, and we’d found a track which we thought would loop around and take us back to the café area in time for lunch.
Although the ground looked very dry, there were wildflowers and masses of butterflies to enjoy, including swallowtails the size of small birds. Only this one, over-confident in its camouflage, would sit still long enough to be photographed.
Ed was a bit worried we were walking through someone’s farm and it turned out he was right to be concerned – a security guard came rushing down the hill towards us when we were nearly back at th café area and insisted we return the way we’d come. It was very hot by this time – high 20s Celsius – and he followed us on his motorbike to ensure we complied. He then turfed us out through a locked gate we’d passed, rather than letting us return to the café. We realised we’d been ejected outside the entrance barriers and, surprise, surprise, the QR codes on our tickets only let us in once. We were worried the security guard would have radioed ahead to the gate and that would be our trip over but the staff there seemed to know nothing about it and Ed was able to talk us back in.
Like something straight out of groundhog day, we had to make our way back through the minor forest to the café for lunch and a much needed sit down in the shade. It was a good thing we weren’t in a hurry as a bunch of elderly men in red guard uniforms (China’s version of the Chelsea Pensioners?) appeared at the same time and were clearly the priority. The tourist stall opposite, at first sight, seemed to be selling a bizarre mixture of different rocks and minerals and chunks of bacon but, on closer inspection, these were rocks too! Calcite with iron carbonate bands, according to the label I saw later in the geological museum.
After lunch we decided to head to the Major stone forest on the other side of the ‘ring road’ along which tour groups are shuttled in electric buses. Ninety percent of the tour groups seemed to have disappeared by this time and it was lovely walking back through the Minor forest to the road.
The major forest was something else completely – gorges hundreds of feet deep with steep, narrow passages in between. We explored some of the nooks and crannies, deliciously cool in the shade. We passed very few people and decided to avoid the viewing pavilion at the top which was just as crowded with tourists as the places we’d been in the morning.
The colour variation on some of the rocks is stunning – a lot of the dark colour due to an algal crust which Martyn talks about in his blog.
By this time we’d all had enough of the heat and headed back in search of a cafe via the huge Geological museum. This gives a good explanation of the formation of the forest and has an impressive collection of stalactites from caverns within the Karst region. It also has an amazing selection of fossils (ichthyosaurs, dinosaur eggs, ammonites etc) and minerals but many are from other parts of China and the labelling in English is minimal.
The pea-flavoured ice lolly I tried at the café near the car park was surprisingly tasty – Ed says the sweetcorn ones are nice too!
Most of us dozed on the drive back to Kunming – plenty of sun and lots of walking. I opted out of going out to eat with a cracking headache but the others had an excellent Korean meal. I settled for what I thought was cheesy bread and fruit from the shops at the bottom of the road – the bread turned out to be sweet and custard filled but the pomelo was delicious so you win some, you lose some!
Xu et al. (2007) Late Permian Emeishan Flood Basalts in Southwestern China. Earth Science Frontiers, 14, pp 1-9. https://doi.org/10.1016/S1872-5791(07)60011-6