Lago Ercina

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Expedition log, Summer 2017

Cueva del Toyu, first drone explorations, Cobijón, and a cheese a day.

Click on, or tap any image thumbnail for a full-size version, or on a video clip to play at a larger size.
15.06 Despite worries with reports of BA luggage problems, gummed-up M40, etc., all went smoothly with Bill’s flight landing at Bilbao just 2 minutes after Mike made it to landside.

An easy drive to Castro Urdiales got us to the Hostal Vista Alegre – stayed at for many years in the past – sadly now a ‘dormitory’ hotel, with the bar boarded up and the restaurant converted to a buffet breakfast area with coffee machines.  Castro Urdiales alleyways were much as before, but our favourite restaurant was permanently closed.

Successfully found a light dinner of ham & cheese, washed down with above average Rioja & Ribera del Duero.  Cheese of the day: small soft sharp goat cheese.

16.06 Up at 8:30 for self-service breakfast which had been prepared the day before. So the food (particularly the bread) was a bit stale.  Apart from butter there was nothing savoury to eat.  Coffee was from the machine. :( The new Vista Alegre was not impressive and we made a note not to return another year.

Sign above Cubilla

Sign above Cubilla

At 9:30 we drove west to Sangazo and then over the saddle to La Cubilla cliff face but it was raining slightly so we decided not to descend the wet and steep path down to the cave (explored on previous trips). Returned back to the autopista and then south via Ramales de la Vitoria with a stop for a real breakfast in Arredondo in the Asón valley (tortilla and white coffee).  A few minutes later we arrived at the Puente Cubera 📌, but there were notices prohibiting the entrance to the resurgence cave there just below the road level.

The roads were now quite dry and there was almost no water descending the waterfall at the head of the valley.  But a few hair-pin bends later we had ascended so much that we reached cloud level and intense fog.  But this cleared at the high point of the pass (1200m) and we descended into the rain shadow.

Sign for Nacimiento del Rio Rioseco

Sign for Nacimiento del Rio Rioseco

Bill wanted to explore the Nacimiento del Rio Rioseco north of Espinosa de los Monteros which we had seen in 2016 but a very long drive up a non-asphalted track did not reveal any features of speleological interest.  Menu del día in the restaurante Sanchez Garcia (€10 each), soup and chicken, cabracho (fishy paté) and anchoas a la romana for Bill.  A bottle of house Rioja included.

Further south out of the mountains we proceeded towards Burgos on good country roads with modest traffic.  Then toll-free autopista to Aranda de Duero arriving 18:00 at a temperature of 37+°C. A long day’s driving.  The Hotel Julia was air conditioned, pretentious compared to Vista Alegre, and cheaper.  But Aranda disappointed with few good-value restaurants and no wine bars(!).  But at 9 we had supper at €50.  Just chorizo and cheese for Bill and a plate of chuletillas and chips for Mike washed down with a good bottle of Ribera Joven (Arrocal 2014).  Cheese of the day: curado from Ribera del Duero.

17.06 Noisy night in Aranda de Duero; some kind of drag-race started just outside the hotel every 30 minutes until 05:30.  Surprisingly hard to find a café open for breakfast at 08:30.  On to Peñafiel to look for an adapter for Bill’s Italian-plug computer power cable; in the end the hardware store we found fitted a standard euro-plug at no charge over the €2 cost of the plug.

Pesquera wine press

Pesquera wine press

On to our only fixed commitment of the trip: a wine tour and tasting at Bodegas Pesquera ».  After viewing the historical wine press we were glad to proceed to the modern cellars at around 13°C, as the outside temperature was already in the low thirties.  Tasting at the end was of the 2012 Pesquera Reserva – excellent.

Onwards west, surprised that the next large village had no bar, and the next, Olivares, only one.  Crossed the river south to Quintanilla de Onésimo de Onésimo which apparently had only one restaurant, where we had a pleasant lunch of filete, etc.

Stopped at the Bodegas Arzuaga Navarro, 1.5km east of Quintanilla – an interesting restaurant, bar, hotel, and shop complex – then back to Aranda in slow traffic and 38°C (12° higher than the average maximum for June) and later to write up the log.  Cheese of the day: a hard white cheese at the tasting, at Pesquera.

18.06 Breakfast at 09:15 in bakery/café, settled the hotel bill, and drove cross-country towards Palencia.
Ribera del Duero vines

Ribera del Duero vines

The Spanish Meseta has good roads over gentle rolling hills.  But the landscape is largely dry scrub-land and the villages seemed to lack bars or shops and indeed inhabitants.  From Palencia the toll-free autopista took us north and we started looking for lunch in Aguilar de Campoo near the southern edge of the Cantabrians.  However, a cycle race had closed many roads so we moved on to Cabria where a bar served us a rich morcilla, jamón, and good Manchego cheese (€29).  Arrived at Llanes at about 18:00 quite tired after the long hot drive.  We reconvened at 9 pm, had a drink on the Don Paco Hotel terrace enjoying the cool breeze of the evening. Decided to skip dinner completely.  Cheese of the day: Manchego.
19.06 Breakfast in two parts, in Llanes.  Then west to the Polígono Guadamia (industrial area) near Ribadesella for our first drone flight.
Polígono hole

Polígono hole

After a short warm-up test flight, flew the drone up the hillside 250+m in about 2 minutes to inspect the possible cave.  Used ‘tripod mode’ to edge with a few metres 📌; both live view and inspection of 12Mpel images later show that, as suspected, it is not a cave.  Very pleased with the quality of the pictures, etc.  Automatic precision ‘return to home’ landed the drone within 20mm of the take-off position.  It would have taken an hour or more through thick gorse and up the very steep slope to reach the place on foot; with the drone the exploration took less than 10 minutes (flight distance 883m).

Mavic Pro after auto-landing

Mavic Pro after auto-landing

Next, on to Llamigo to scout a possible new approach to Cueva Negra from the south; found a good track but it ended abruptly at El Acebaliegu. No other likely track, so on to Riensena and via Mestas to Posada for a snack of Cabrales cheese.  By now very hot (for Asturias): 30+°C.

Next to Ribadesella to find that our two favourite restaurants (Rtes. Covadonga and Mesón Miño) have closed; managed to find lunch of pig & egg in various forms.  Back to Llanes to upload/backup data, write the log, etc., followed by paella and fish at Rte. Canene.  Cheese of the day: Cabrales.

20.06 Hot again: 29°C rising to 33°.  Southwest via Posada and Meré to Covadonga then up to Los Lagos.  Roadworks, cattle, and the heat made it seem a longer journey than usual, but the spectacular limestone at the lakes made up for it, as always.  We took a panorama print to give to the family at the bar María Rosa, descendents of the owners in 1973, but unfortunately no one who recognized us was there.

Goat near Lago Ercina

Goat near Lago Ercina

Given the heat, we decided a walk to Ario or Forcau was impractical and instead settled for a circumnavigation of Lago Ercina, adding some elevation over rocks to the South and to the East.  A cold beer on returning to the bar was much appreciated.

Back down to Covadonga, dodging many cows and the occasional bull, then on to Mestas de Con for menú del día with vast portions of garbanzos, fish, meat, etc.

Slowly made way back to Llanes; a light supper of gambas al ajilo and cheeses at La Amistad.  Cheese of the day: toasted goat cheese.

21.06 After coffee in the Mexican bar we drove east to La Franca but access to the small depression north of the village did not look promising and a local told us there was no cave.  Perhaps a return to Cueva del Espinoso (access via Estate of same name) could be in order.



On to the presumed Cueva de Meaza sink south of Comillas 📌.  The track down to the stream could probably have taken a car but we walked down but on crossing the water there was no path downstream to the sink some 400m away – just trees and thick and wet undergrowth.  So up the hill again to approach from the north, but to no avail. All this walking in the sunshine and heat worked up quite a thirst, slaked with a beer in Canales.

Bill in Cobijón

Bill in Cobijón

At this point we were on our way to the sink at Cobijón 📌.  Bill waded down the streamway, 2m wide and 8−10m high.  Voice contact became impossible after 8m even though we were in sight due to echos and the sound of falling water outside the cave.  The water wasn’t clean but it wasn’t horrendously dirty.  There were plenty of insects swimming in the pools including dragonfly nymphs.  The cave was deliciously cool compared with the outside air.

The passage curves round to the left and water level rose to thigh level.  Bill spied a free climb on the left leading to a high level rock bank which likely bypasses the deeper water.  After taking photographs Bill returned to Mike rather more quickly than his entry knowing that the depth of the water was fairly uniform.

Cobijeru entrance

Cobijeru entrance

Our enthusiasm for exploration was not diminished and a stop at the Cobijeru caves at Buelna 📌 was required as Bill had promised to wade down the stream of another sink.  But this was not to be as there was a climb down into an evil looking pool of unknown depth.  Mike concurred.  A paddle in the sea water at the inland beach to wash completed the morning’s exploration and we stopped at Casa Poli in Puertas de Vidiago. Here we had jamón Serrano, patatas ali oli, and a cazuelita de fabada.  Walked around Posada before heading for Llanes.  Simple supper of patatas al cabrales.  Cheese of the day: Cabrales.
22.06 Coffee in the Mexican bar at 9:00.  An overcast morning so south seemed a good direction; perhaps to walk above Sotres.
Queso Azul de Pría

Queso Azul de Pría

The Cheese crawl began at Bar Ramón in Carreña where somehow we managed to devour a large plate of Queso Azul de Pría.  By the time we reached Arenas the sky had not cleared so we proceeded east to Panes and then Suarías with a view to explore the large depression 1.5km SE of the village, at 📌.

The map doesn’t show it, but a meandering streamway drains the depression and sinks 📌 – but there is no cave.  However, much of the area is littered with smaller depressions and some are up to 20m deep.

Suarías sheep (5)

Most of the valley is grazed by sheep and cattle and the wet grass was short, but elsewhere the vegetation is typified by brambles, bracken, gorse and trees.  No cave entrances found.  However it was noticed that the catchment area seemed too small to supply sufficient water to the stream.  So we conjecture that in the woods to the south east there may be an undiscovered resurgence at an altitude of say 350m on the limestone/sandstone boundary.  This system could be fed from various sinks at Majadas de Rejedas in the Honda de Valmayor to the south at about 600m.

Lunch at Casa Gloria in Camijanes where we were recognized immediately from previous years.  The service was absolutely stellar.  A single plate of lomo each, washed down with ‘La Planta’ Ribera del Duero. Mike even ate his lettuce and other vegetables! Thus fortified we visited both upper entrances of the Sistema del Toyu (Venta de Fresnedo) clearing away the brambles for a subsequent trip.  The ‘Torca’ entrance near the barn looked quite accessible without special equipment.

Dinner of rich fish soup (“best ever”) at the Salero restaurant in Llanes followed by merluza (Mike) and bocartes (Bill).  Cheese of the day:  Azul de Pría.

Picón de Bejes

Picón de Bejes

Woke to rain, so after coffee at the hotel we effected the standard procedure for the weather: head south.  As expected and hoped-for, the rain stopped by the time we reached Panes.  Plan A was to do a high walk near Bejes, but when we reached La Hermida the cloudbase was far lower than the walk’s start so we decided to have a planning session over Picón de Bejes and Rioja.  Excellent Picón, though a touch drier and bluer than ideal.

Backtracked down-gorge to Urdón, and had a good walk up the Urdón river valley – turning back in order to get back to La Hermida in good time for lunch (and also because a particularly steep bit was reached...).  Good lunch, then up to Bejes to confirm the weather, etc.

Bejes drone hole 1 (7)

Bejes drone hole 2 (6)

On the way back down we noticed a couple of intriguing holes in the cliff face above Puente Pumpedrei (at 📌 and 📌); ideal for investigation by drone.  A few minutes later the drone was in the air and photos and videos were taken.  Both holes look interesting; the more easterly one apparently with a passage curving away, and the other possibly a passage but also with a built wall or floor.  The latter artefact is not visible from the road, only by drone – and is strange because the hole is some tens of metres up the cliff so this could not be a goat pen, etc. – we conjecture that with its commanding position above the road it may have played a part in the post-Civil-War guerrilla activities.

After packing up the drone (5 minutes), back to Llanes, pleased with the day’s activities and with avoiding the rain.

Dinner in Almacén with its famous boletus con Picón for Bill and fritos de pescado for Mike.  Cheese of the day: Picón de Bejes.

Mike before descending Toyu

Mike before descending Toyu

Real caving today with an attempt to explore Toyu upper series and descend the 4m climb leading to the streamway and to do the ‘through trip’ entering at the Torca (barn) entrance.  An ideal cool day with overcast skies and temperature of about 19 degrees.  It took just 35 minutes driving to get from Llanes to Venta de Fresnedo. The undergrowth which previously blocked access to the entrance was now clear thanks to our efforts on Thursday, but the descent was steep, somewhat slippery, and with some quite vicious brambles. Just inside the cave there were the usual pile of animal bones testifying that not only elderly speleologists have difficulty negotiating the obstacles.  Bill managed to slip on mud within sight of daylight and gashed his elbow.

Bill at Casa Gloria

Bill at Casa Gloria

Route finding was difficult but traces of previous muddied boots suggested the way was straight on, stepping across a drop and through a ‘hole’ in the wall.  Beyond, there appeared a dry vadose passage (keyhole) some 4m high which would require traversing at height. After discussion we decided to try the other entrance.  Here we proceeded without difficulty to the main chamber and explored down to the 4m climb.  We free-climbed this in the 1980s but even with rope and jammers it seemed a daunting prospect 30+ years later.  Back to the main chamber to admire the reflective ‘moon milk’ and golden relative. We then made another attempt to connect to the Torca entrance, without success, and retreated after about an hour underground.

Quesos at Casa Gloria

Quesos at Casa Gloria

Found a pleasant bar at El Mesón de Celis.  Lunch in Casa Gloria again with a whole leg of cabrito for Bill and chuletillas de lechazo for Mike and ‘La Planta’ Ribera del Duero, followed by a plate of 3 cheeses:  sheep, goat, and Picón (the latter sharper than usual).  Cheese of the day: Casa Gloria’s sheep cheese.
25.06 First through Posada and over the medieval bridge at La Herrería to El Allende and on to Samureli (the hamlet) to view the Jou de Cuanda 📌.  Backtrack to the Cueva Samoreli (the cave) by car and on foot to 📌 with the intent of getting drone pictures of the impressive entrance.  Unfortunately with many ‘new’ trees and undergrowth there was little visible, so we abondoned flying there and headed for El Mazuco instead, with a short exploration of Cueva de Caldueñín on the way.

Above Boriza; flyers at top right

Above Boriza; flyers at top right

It being Sunday we decided to stop at the bar to secure a table for lunch later, then continued on foot to a point above Cueva de La Boriza.  Here we found a clear field to fly the drone, and although unable to approach La Boriza itself because of trees we did record a higher-level cave entrance in the cliff face 📌 – likely an abandoned resurgence.

Semi-packing the drone, we returned along the track towards El Mazuco, turning off to the west to Pozo de Fresno 📌 with its prominent Ash tree.  Here a drone flight captured a straight-down video of the pothole which was pleasing (see video clips). After a bit more aerial reconnaissance, brought the drone back to near the take-off point and Bill had his first hands-on the controls, marvelling at the ease of flying it.

El Mazuco <i>costillas de cerdo</i>

El Mazuco costillas de cerdo

By now it was 13:50, and we were soon sitting down to lunch at El Roxin.  It being weekend the wood-fired grill was hot and (along with patatas ali-oli and criollo) very tasty costillas de cerdo were enjoyed.

A very light supper of Manchego at El Pescador.  Cheese of the day: Manchego.

26.06 Rained all night and most of the morning.  Had coffees in hotel and drove south at 11:00 to Arenas de Cabrales where it was almost dry.  But the mountains were shrouded in low cloud so any trip up to Tielve and Sotres looked pointless.  So we retraced our tracks 5 km back to Carreña where we perused the restaurants.



Settled on one offering cachopo (a Spanish-style breaded veal Cordon Bleu) that seems to have appeared on many menus this year. The restaurant offered several variations; Mike’s contained cecina and Vidiago cheese, and Bill’s had bacon, mushrooms and Cabrales. The house wine was not so good and we left some.
Playa de Toró

Playa de Toró

But we had a good glass of Ribera at Sidreria Jovino in Posada, where the sun finally came out – inspiring Mike to stroll to Playa de Toró on return to Llanes.

Tabla de queso at the Sidrería nearest the old Rte. Gale¢n. Cheese of the day: Vidiago.

View from Tresviso

View from Tresviso

The streets were wet but at least it wasn’t raining so coffee in ‘El Latino’ (Mexican bar which used to belong to Antonio).  Clouds were low but Mike found a web-cam on the WWW showing blue skies above Sotres.  As we drove it started raining sporadically and visibility in the mountains did not look good.  But it was our last day so we drove up to Sotres then Tresviso in the rain, mist, and 13°C anyway. The webcam was, sadly, a case of ‘fake views’.

The road through limestone valleys was beautiful as always, but the cow tracks through the gorse were slippery and overgrown.  And visibility was limited – quite impossible to reconnoitre a high level route to the Majada de Tordín. So back to Arenas de Cabrales again, and lunch at Sidrería Calluenga.

Tortu Cabrales (a kind of crispy pancake made of maize flour, topped by a chunk of Cabrales) for Bill and patatas al cabrales for Mike, washed down by the ever favourite ‘La Planta’! In the afternoon the sun made a weak attempt to appear, so we visited Playa de Poo, but by 20:30 it was raining hard again.

Cheese of the day: Cabrales.

28.06 Packed and on the road to Bilbao by 10:00.  First stop the ‘Garganta de Job’ spotted on the map earlier; 1km north of Prellezo, a few km west of San Vicente.  Not sure if we found it, but did find Playa de Berrellín, a peaceful idyllic little beach among rugged limestone cliffs.  A couple camping on the beach and a guitarist set the tone.
Playa de Berrellín

Playa de Berrellín

After walking around we decided that to reach possible caves would take more time than we had available, so on via San Vicente to Comillas for elevenses.  Broke the journey again at Puentecilla and Castro Urdiales, the latter to satisfy curiosity as to the location and name (‘Marinera’) of the restaurant we ate at on the first day of the trip, and to reprise the tabla para dos (ham and cheese) we enjoyed then.  Arrived at BIO at 15:03; plenty early enough as Bill’s flight was delayed until 17:02 and Mike’s was scheduled for 19:30.  Driving time a little over two hours, including diversion to a petrol station just NW of BIO.  Bill’s flight ended up arriving 1 hour late; Mike’s 25 minutes early.  Cheese of the day: a hard, probably sheep, cheese in Rte. Marinera.


  1. Exchange rate: 1.14 (compared to 1.425 in 2015 and 1.26 in 2016); 88p = 1 Euro = 166 pesetas (189 pts/GBP).
  2. Weather: well above average temperatures for the first week, then cooler and wetter than average.
  3. The drone we flew was a DJI Mavic Pro ».
  4. The pictures in this log were taken using a Panasonic TZ100 camera, a Panasonic LF1, various phones, and the drone.
  5. Specific GPS positions are shown by a pushpin symbol (📌) in the log above – click on the symbol for a Google maps view of the fix.  These positions are also listed on the Speleogroup site list page with coordinates in °,′,″ degrees using WGS84 datum and in UTM coordinates; see Coordinate systems.
  6. The Urdón walk was recorded as a GPS track although with poor results due to the extremely narrow gorge; GPX tracks of the drone flights may be available if you contact us.
  7. Fixes and tracks were recorded using a Sony Xperia XA Android ’phone using the MyTrails app (or by the drone, for drone flights).
  8. This log was almost entirely edited in the field on an ASUS T-100 ‘Transformer’ notebook, using the MemoWiki » extended Wiki notation which is then processed by a Rexx » script to generate the HTML for this web page.

Expeditions to the Picos de Europa and elsewhere since 1973.
Please e-mail Mike Cowlishaw ( or Bill Collis (
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This page was last edited on 2022-03-23 by mfc.