The Ayllón Mountain Range or Sierra de Ayllón is the of the chains that conforms the Spanish Central System Sistema Central, on its easternmost edge.

The Central System was formed during the early Cenozoic Era (the current geological era) in a process called the Alpine orogeny – when the African tectonic plate crashed against the Eurasian plate, a geological event that gave way to the main European and Asian mountain ranges, from Spain in the west to Java in the east.

It rests on a granite base that became first folded, then fractured during the formation of the system. As the rocks eroded, the sediments deposited and formed new sedimentary socks. Other processes that influenced the formation and shape of the ranges have been the action of glaciers and rivers and the subsequent weathering of the exposed rock.

The most common rocks in the Ayllón Range are granite, as expected, gneiss, and slates, some of the latest mixed with clays. For centuries, the villages of the area have been known as “black villages” (pueblos negros) as slate has been extracted to build them. One of such villages is Campillo de Ranas, which translates to something akin to “Little Field of Frogs”, and one of the neighbourhoods adjoined to them is Roblelacasa (literally Oak-the-House).

Roblelacasa happens to be the start of a hiking route to one of the highlights of the range – the Pozas del Aljibe (Aljibe Pools), with Aljibe being a word of Arab origin that means “cistern” or “well”, so not that original a name, I guess. I had been wanting to see these pools – also called a waterfall – for a while, so I decided to drive off and hike the route to see the Aljibe, which is considered one of the most beautiful in the centre of Spain. The hike is about 3.3 km each way – but guess what? I ended up taking a detour or two (≧▽≦). The pools are formed by the Soto Creek, Arroyo del Soto, a tributary to the river Jarama which in turn flows into the river Tagus.

Off I went. The drive took about an hour and twenty minutes. I left home around 8.20 and arrived in Roblelacasa around 9:40. The drive went well, most of the road was a nice national road, and as it was a local holiday traffic was scarce. Some people were in a great hurry though, ignoring speed limits. This was my first time driving on my own with the Sat-Nav, and it went all right. However, as I drove towards the range, there was a dark cloud I did not like one bit.

Just after reaching the “village”, I found a parking spot right behind the panels, as the expected parking lot was closed off. I had packed some frozen water, biscuits, the camera and my cap – but I had forgotten the umbrella, and it was a bit grey. I decided to leave taking pictures of the village for later, and I started walking just behind a couple who had arrived virtually at the same time, but I passed them as they stopped to take pictures.

The route is officially named “PR-GU 09: Sendero de los pozos del Aljibe” and it is part of the natural park Parque Natural de la Sierra Norte de Guadalajara. Upon leaving Roblelacasa, the first couple of hundred metres crossed fractured and weathered rock before crossing a symbolic gate that marks official the beginning of the trail with a white and yellow double-line. Then, I walked onto a gravel path flanked by the remains of old fences. To the left opens a valley, and looking back I could see the village, in black.

The route widens into a dirt track that is obviously travelled by car sometimes, as the range peaks stand in front of you. There are no trees but a lot of bushes and aromatic herbs, and as you walk the scent is very pleasant. Then there is a small forest and a second barrier, which marks the turn where you are going to start climbing a new hill – slowly, the terrain rises to your left while it lowers on your right, giving way to the creek’s valley. Just before reaching this I passed a family who had started walking before me.

Eventually, you reach a fork in the trail, with the choices of going left towards the waterfall or right down the valley to see a former dam-turned-bridge. I went to the waterfalls, figuring out that I could always go down to the dam on my way back. The track became narrower and rocks started popping up again.

I wandered off the trail (you can see the markings on the upper picture) a couple of times because the views were neat, but a few minutes later I crossed a little bridge to get access to the waterfalls viewpoint on the left-hand-side bank… which was closed. Believe it or not, the actual waterfall area had quite a few “do not walk, falling risk” signs that… okay, I have to be honest… I pretended not to see. I hiked up to the viewpoint and sneaked a little to the side to see both waterfalls. As it has been storming, there was a good amount of water flowing, so the view was pretty cool.

The upper waterfall is about three metres high, and the easier one to see, without needing to ignore any warning sings. When I walked up to the viewpoint I got an amazing view of both the upper and lower waterfalls, the latter being about 7 metres high. It is easy to see how they are called either waterfalls or pools.

Remember that I said that I passed a family on my way up? This is kind of important because it means that I was basically alone in the waterfall area for about ten minutes, enough to take a good bunch of pictures from both banks of the creek without having to edit people out. I was however very cautious about cracks and faults. I think most of the rocks in the area are quartzes but my geology skills are a bit rusty.

As I decided to turn around, the family arrived, and so did the couple I had first passed and another group that must have started behind me. That was okay because I was done, and on my way back I could stop for a lot of pictures that I had not taken before. Here you can see the difference between the quartz /gneiss (surrounding the flowers) and the slate (in the middle).

Also, at some point before I started my return hike, it cleared up. All of a sudden it was hot so first I shed off my sweatshirt and when I reached the crossroads again I really needed a drink and some shade – but I had packed water and the cap, so everything was fine, and I could divert to see the old dam, Presa de Matallana over the creek Soto – from both sides. This must have been around 11 am.

I turned back towards Roblelacasa and I noticed that the wide track was a bit more “upwards” than I had noticed the “downwards”. I had a bit of a tired moment as I adjusted to hiking up in the heat – why is it that normal hills tire me more than uneven paths? But it was over in five minutes and I was back in the village a bit before twelve. On the way now I stopped to take pictures of the flowers and bushes around, and of the valley that Roblelacasa overlooks – and ran into four or five more groups / couples who must have started walking around 11, so it was a good call to get there early.

This is how the village looks in the light of day, just before I took the car and drove back around noon. I decided that I would go back to the area some other time to explore other villages around, mainly Tamajón, which is reported to have an interesting geological area, and some other black villages.

Oh, and a the pictureless anecdote of the trip, for obvious reasons. There were a lot, and I mean a lot of “caution wildlife” traffic signals, and on the drive there I thought that I had very rarely encountered any wildlife crossing the road. I had also not come across any wild (or domestic) on the trail, aside from some little lizards and a few pet dogs with their owners. Well, good thing I was driving a good 10 kph under the speed limit, because on the drive back I had to yield to a wild boar! Live and learn (to drive slowly in wildlife areas)!

Driven distance: around 130 km (2h 30min)
Hiked distance: 6.7 km / 11,106 steps (2h 20min)