Lago Ercina

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Expedition log, Summer 1983

A transcription of the Speleogroup logbook.
La Franca first, then Llanes. Purón, etc.

29.07 Bill potters around Castro Urdiales, etc., until Mike arrives at Bilbao airport (17:20).  Drive west, stopping for a tinto at Santillana.  Decided to drive on: arrived at La Franca campsite 22:30, to El Horno for dinner at 23:00.
30.07 Up at the crack of dawn (08:00) then to Purón.  Followed the track up the hill for the best part of an hour (very hot and sticky walking, sheep flies) to the depression containing El Cuevón de Pruneda (alt. 273m).  Explored the upper series for some distance using flashlights; Bill’s porterage over pools much appreciated by Mike (both in dry kit).  Very nice clean cave.

Back down the hill to Purón, then to Llanes for lunch (Trout & Steak, still only 550pts). Off to Barro beach for some sun and a swim.  Next to Rales to meet Leopoldo & María-Carmen (who were married just a month ago) and their family (friends of old).  Went with L and M-C to some bars for cheese and sidra, Cuba Librés, peanuts, etc.  Finally back to the campsite for a late meal (garlic with bonito) and a stroll down to the sea.

31.07 Up at 08:00 again(!!!) And to La Fuente/Venta Fresnedo by 10:00.  While at Venta Fresnedo, we learned that some years ago (10+?) the Toyu water backed up so much that it flowed around the corner of the hill and flooded over the road, which dammed a huge lake behind it.

After leaving a copy of [Toyu?] survey in the bar, thrashed around in the undergrowth for a while before finding 📌, Cueva de los Marranos » (alt. 128m, Rio Lamasón 120m), which turned out to be a rock shelter with various dry passages and chambers, a toad, and many tree roots.

Back to La Franca to clean up, then to San Vicente for a lunch of fabada and lomo de cerdo.  Back to La Franca just in time for a thunderstorm, so spent the remainder of the afternoon playing cards in various bars.  To Llanes for paella for dinner, and dodgems.

01.08 Up foolishly early again; decided to move camp from La Franca to Llanes (Camping El Brao) to be nearer town, restaurants, etc.  Changed cash and investigated local environs, 3-course lunch at Bar Uría restaurant (soup, potato stew, truchas). Spent afternoon playing cards with Mercedes people and others, catching up on sleep, etc.; dinner (bonito and a very pleasant Rioja Blanca) at El Horno and tea to follow.  Looked at “La Franca Fiesta” but not even a stage.
02.08 Left after a good night’s sleep for Purón and the foreboding Cuevón – 35 minutes up the now familiar hill.  Plunged into the murky entrance pool before reaching lovely smooth rock and streamway (all spiders having been removed on the previous trip).  With good lights but also sunglasses we pressed on down small climbs and deepish pools gradually evolving into ‘critical depth’ pools (swimming) – all this in dry suits!

Passed a fine slide which Bill optimistically called the first free-climbable pitch and down another 1m step into a deep pool.  After more deep pools we reached an indisputable pitch, complete with record of a Spanish group who had explored the cave in 1981 (OUCC explored it in 1970/1 »).  We pottered around the pitch, and Mike went half-way down, and we both agreed independently that it was not free-climable, even liberally (to quote Ian Rogers).

By this time the cold and wet was taking toll; at the 1m step on the way back, Mike ‘elegantly levered himself out of the pool’ and Bill, being no sportsman, said (and he quotes): “You’re making heavy weather of that, Mike”.  Twenty minutes later (!!) after four direct assaults (the last of which was assisted by numerous slings held by Mike), Bill stripped himself of all impedimenta (glasses, carbide, altimeter, rucksack) and then slipped and wriggled using an underhand route up through the narrow hole in the lip of the step.  This was insufficient to go the whole hog, and further assistance by way of slings (and bruises on Mikes hips) was required before the mere 1m of raw rock was finally conquered.  Exit Bill very much staggering from cold and exhaustion to the haven of soft grass and gentle wind (but no real sun).

Not beaten yet, however, the intrepid pair went on to investigate the other cave of Purón, Cueva Culebre (in log as ‘Los Arcos’), though without lights a full exploration had to be postponed.  (This looks like potentially a significant ancient cave, now bypassed by the stream but not by local couples in need of solitude – according to our shepherd informant.)

Back to Llanes for a 15:00 lunch of fabada, tortillas, y escalope.  Then to the bar on the beach (El Toró) to write the log.  Festered until dinner time; forced ourselves to El Horno again, then cards in the bar until thrown out.

Lago Ercina, 1983

Lago Ercina, 1983

Left for the Lakes at 10:30.  A cloudy morning, but an inviting blue sky just over the mountains beckoned us to Covadonga and up the familiar road to the Refugio.  No sign of cavers camping.  Snack of v. good cheese and wine was had below in the Refugio bar (still large 200 cc. tintos, as noted in 1982, 20th July).  Sat on a rock pillar outside to admire the view, bask in the sunshine, and photograph the cows.

Still no sign of cavers, so back down the hill.  Decided we had no appetite for lunch at Arriondas, despite Bar San Remo still offerering menú del día for only 400pts (up 50pts from 1982). A couple of drinks in Posada then to Llanes for a swim and a sunbathe.

At 17:30 Bill went off to Cueva los Arcos/Culebre.  Dressed in ordinary clothes he promptly slipped down the entrance mudbank into the river! Having thus verified that the cave is a resurgence, he paddled up to a muddy meandering streamway.  Too dirty to continue.  Explored length 30m; “well worth a visit in 1993”.

To Rte. Covadonga for a pleasant meal: chicken soup with lots of Jerez for Mike & entremeses de variadad (cooked meats, etc.) for Bill, followed by paella for both.

04.08 Blue skies, hot sun, and a sore toe decided us against the planned (long and sheep-flied) walk up the Latarma valley, so, once more unto the beach, dear friends ...

After two hours of sun (carefully recorded on a unique sundial), into Llanes for a menú del día of fish (Rape) and steak at the restaurant next to the bridge.  Back for a walk along the cliff, during which Mike carelessly sprained his ankle (while looking for a cave, of course!).  Back to the bar for teas, coffees, beer, tintos...

Eventually left for El Horno for the expedition dinner (via La Franca, to return large-deposit Kas bottles).  Hot peppers & anchovies for Bill (later regretted) followed by bonito; fabada for Mike (also later regretted).  Wine was “Monopole”, a rather oaky white Rioja. Not a good night’s sleep.

05.08 Got up at 07:00 (unheard of!), after which Bill is amazed at the traveling speed of hot peppers.  Despite drizzle, all tents were packed away and we were ready to depart for the airport at the planned hour of 08:00.  Horror! The campsite office (which held Bill’s driving licence as surety) was closed.  Into Llanes for coffee & pastry, returned to find the office still closed at 08:35. “Perhaps it will re-open at 9”, someone said.

Fortune shone at 08:40, and we were on the road at 08:45, somewhat behind schedule.  Drizzle continued.  The traffic did not.  Arrived in the centre of Bilbao 12:50, the very time the plane was due to take off.  Arrived at the airport by a somewhat circuitous route at 13:05 – too damned late! Depression reigned; investigated all alternatives (via Bordeaux, Biarritz, Madrid, Vitoria, etc.).  Best option was to reserve a BA flight for 09:25 the next morning, Saturday.

Vineyard near Haro

Vineyard near Haro

What to do next? Decided to head south to Rioja, to find sunshine and wine.  A new motorway bridge to the west took us onto the Zaragoza motorway, stopping at services for lunch.  Soon (averaging more than twice the speed of the morning’s drive [sigh]) arrived among the vineyards of Rioja.  Investigated much of Haro, by car, but found it unexciting – but at least the sun was shining! Stopped for an obligatory tinto at a local Hostal-ry, then in a vineyard for photos. Next, north and east via Treviño and over the Puerto de Vitoria (disappointing).  Down through the outskirts of Vitoria, and east to the Parador Nacional (a cool, pleasant, converted palace) for much-needed showers etc.  Sherries in the bar (240pts), stroll in the sun (to dry hair!), and delicious iced coffee.

Finally decided on dinner ‘out’ at a local roadside restaurant just down the road (reached after an eastward excursion and leading several other cars around a one-way system the wrong way, and finally onto the main road via an exit slip-road!).  Dinner of entremeses & omelette (Bill) and fish soup & lamb chops (Mike), all good and washed down with a very pleasant Rioja and much talk.

06.08 06:30 start to be sure of catching the plane.  Uneventful run to the airport, less than an hour.  Time for coffee before Bill drove off into the sunrise.  Uneventful flight, but bumpy before landing at Gatwick.  Transferred to Heathrow to pick up car, a ride enlivened by Irish bus driver.

On return, found that the flight Mike had missed on the previous day was, in fact, cancelled – Bilbao airport had been closed! (21.09 Iberia eventually refunded the ticket for later flight.)

Personnel: Bill Collis & Mike Cowlishaw.

Other log details: Exchange rate 216-222 pesetas/GBP.  See also 1982 log (same book).

Expeditions to the Picos de Europa and elsewhere since 1973.
Please e-mail Mike Cowlishaw ( or Bill Collis (
if you have any corrections, suggestions, etc.   See also the SpeleoTrove speleology section ».
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This page was last edited on 2019-07-06 by mfc.