Lago Ercina

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 The Battle of
 El Mazuco

Expedition log, Summer 1975

This is an account of the 1975 Oxford Expedition.  Its six-week mission, to explore strange new caves, to search for the paintings of prehistoric civilizations, to boldly go where no man has ever been before.  Transcription of the expedition log.

18.07 Left Winchester 7:30pm in Bill’s white 3-wheeler Reliant van.
19.07 Up at 04:30; boat to Le Havre.  Off boat 07:30; in Spain by 23:25, camped Rosaleda (near frontier).
20.07 Left Rosaleda 10:00; at Posada 17:05, met Steve Norton and Martin Laverty who had arrived just 10 minutes earlier. Celorio Fiesta for a brief visit (boring). Then to Llanes for meal. Camp site at Rales field (as in 1973 and 1974).
Tinganón surveying

Tinganón surveying

Off to Tinganón for surveying; in at noon – undergrowth not too bad.  Surveyed to grade 5d (we thought at the time), out at 17:30. Standard curry meal then went to Posada for a few drinks at Acuario; back just as thunderstorm started.
22.07 Tuesday.  Up at 09:30.  Still heavy rain, so off to the bar in Rales to calculate some of the Tinganón survey figures: closures awful.  Rain stopped, so Bill later goes to Llanes (twice) to check for arrival of Bluewater parcel (for Victor).  Steve and Mike get some prusik practice on the cliff above west San Antolín beach.  Martin mended wetsuit and had boots thrown into the river by a local lad.  Later still, to Rales bar.
23.07 First to Llanes for shopping to replace Martin’s boots, lost in river the previous day. Then Mike, Bill, and Steve into Rales system – collecting water samples at bottom and middle of streamway and also at Samorelli sump.  Then back down streamway, exiting at Fuentica. Four and a half hour trip.  Curry and Rales bar again.
24.07 Eventually went to Trumbio area.  Martin & Steve had a look for Cueva Rota – found a 10m-long hole which was probably it.  Meanwhile Bill & Mike descend Trumbio (2.5 hours), taking a few notes and cross-sections.  Strenuous scramble on boulders etc. plus a 10m pitch into huge chamber 60m × 60m × 200m and a stream that sumps.
25.07 Bill walks to Rales upper sink and Polje (beyond Samoreli) – Vizcaina; Steve & Mike to Cue – found sea caves and suitable abseil/prusik practice cliff.  Martin got paid for boots. Posada fiesta that evening.
26.07 Swimming + sunbathing + sunburning at Barro beach. Drove to El Mazuco for a walkaround and sight-seeing trip, then back to Barro for steak and chips supper.
27.07 Drew up Tinganón working survey in the morning; Steve attempts to get bread in Posada (unsuccessful as Sunday).  At 5pm the secret weapon of Rales (Steve & Martin) took part in a Rales vs. Balmori football match; Bill and Mike took photos [none of which seem to have survived].  Spaghetti bolognese for supper.
28.07 Off to the Llamigo area. Steve & Martin walked looking for new caves – several caves and other suitable sites were seen and heard about – worth a return visit.  Mike & Bill carried out a grade 3 survey of Llamigo cave (250m surveyed). (Only grade 3 because the OUCC clino didn’t work, but the cave was horizontal).  Drew up survey in the evening and ate beef Newton! Cracked a bottle of Sidra and three eggs.
Rales campsite

Rales campsite

First event of the day – a snake in Bill’s tent about 60cm long, brown and evil looking – eventually chased off with a long branch. Very hot walking around Vizcaina and Rales system: Martin, Steve, Bill went up to the Vizcaina sink (50m grade 1 survey made) – very wet, and choked with flood debris (wood).  Martin then walked around to La Fuentica, messed around in entrances, and found a new passage (up for 10m) which connected with the upper series.  Meanwhile, Steve and Bill foolishly climbed up to Samoreli in wetsuits, got lost, but met a farmer who “saved their lives” with copious quantities of water.  In Samoreli, looked at the ‘sump bypass’ – definitely previously explored – and surveyed the upper entrance passage at grade 3b.  Then down Pozo del Molino and streamway to detackle and take photos.  ‘Lack of communication’ on the lower pitch. “Bill, the rope’s not long enough” ...  “I’m coming down now...” ... “YOU *?!!*?!” [sic].  As neither were carrying prusikers (fools) the last 15′ down was a little awkward, and the rope was left a-hanging in the void.  Return trip after a meal and a beer, equipped with dozens of prusikers, to retrieve said rope and descender.
30.07 Off to Fuente Dé and 1 mile up using the Teléferico. Fine weather; invesigated threshold of a mine and snow patches, poljes etc.  Then in 20 minutes a thunderstorm blew over – hail; rain (lots); lightning etc. and a walk in the rain in thunder. When we eventually got down, stopped in La Hermida for paella (628pts all total) and arrived back in Rales at 23:30 in time for a quick drink in the bar and to investigate lighting habits of glow-worms.
31.07 Returned to La Hermida gorge and looked at Spanish group’s map of Pozo del Infierno at their campsite across the Coto del Infierno bridge.  We then took an hour to climb up the mountain and find the cave. Handline too short on 2nd ramp.  Continued to PdI 2 via handlined climb from water chamber – via various lakes and boulder ruckles to “el final”, the sifon.  Actually, the so-called sifon is merely a duck, and bypassable too, so we have agreed to return tomorrow to show the Spaniards the lake which lies beyond.  Bill won ‘Dirty Pig of the Day’ award for having a s..t 100′ from the entrance and within sight of daylight.
01.08 Mike & Bill arrived at Coto del Infierno at las dos y media (14:30) and chatted for an hour before attempting the climb to Pozo del Infierno.
Pozu del Infierno campsite

Pozu del Infierno campsite

7 Spaniards carrying rucksacks and boats etc. accompanied us to their campsite where they put a tent up(!) in a big dry chamber, the ‘Talps gallery’.  On the way Mike broke a screw on his battery top – write off! Generous Spaniards lent him a carburero de auto-presión complete with helmet.  Exploration then commenced. At the lake 2 Spaniards pumped up a substantial dinghy and Mike & Bill, in wetsuits, pushed them across.  One is just out of one’s depth in places and the water is very cold.  As expected there was a boulder ruckle at end of the long meandering lake.  One side passage went 50m.

In Pozu del Infierno

In Pozu del Infierno

We left the cave at 21:00, climbed down the mountainside in our wetsuits, and had a much-needed swim in the river at the bottom. Then have supper with 4 of our hosts in the valley below – a simple dish of chickpeas in packet mushroom soup; so hungry it was one of the best things we’d ever tasted.  Left at 00:30 and arrived back in Rales at 02:00.
02.08 General ‘Recovery’ day.  3 went to Llanes after meeting Steve Evans on the road between Posada and Rales; shopping, money-changing, photocopying of surveys, etc.  Set up large tent and then spent evening in Rales bar.
03.08 Spent morning packing then off to Lago Ercina in the mountains via Cangas de Onís. Set up camp at ‘old Spanish campsite’ to southeast of lake, then down to the local lake bar, “María Rosa”, where locals were fascinated by our carbide lamps.  Bill, Steve E., and Martin had a walkabout – in the rain.
First camp near Ercina

First camp near Ercina

“Arriba, arriba” at 07:30 ... National Park Warden wakes us, objecting to our presence: told him we were waiting for the Spanish cavers and he agreed to let us stay the day. Then met a group of French cavers from SCAL (Spéléo-Club Alpin Languedocien) Montpellier who were camping in the car-park. Later Bill walked towards the Dobra gorge (without getting there); Martin also had a walkabout in the same area.  Mike & Steve N. followed Steve E. to a cave noticed the day before.  Unfortunately the latter could not find it & so walked for two hours over the mountains. In the evening all went down to Cangas for a meal after moving camp down to the car-park and having a long chat with the French.
Ercina and Peña Santa

Ercina and Peña Santa

Those sworn to swimming in the lake chickened out with excuses such as ‘there are fishermen (3) along the bank’, ‘it’s too dirty’, etc.  Bill & Steve N. went down to Cangas for petrol, money, and food at a restaurant there.  Mike spent four hours looking for Pozo Palomeru – unsuccessfully.  Martin & Steve E. set off towards Forcau.  Found very promising extensive area of limestone with shafts etc.  Meanwhile Bill & Steve N. looked around the Beyos Gorge and found Cueva de Buseco – large and dry.  Not fully explored as ‘populated’ with local kids.  Very merry evening with French and some Spaniards.
06.08 All looked for Pozo de Vega el Forcau, eventually successful after descending several shafts and Bill had asked a shepherd.  Exploration was hampered by the heat of the sun and hangovers; prepared tackle for exploration the next day.
07.08 Got up at 07:15.  Joined the French from SCAL at 09:00 (Philipe Altairac, Veronica, Martin Figere, Sallia, François Henry, Gilbert, Pierre +2, Alain Ottan).

On the way to Forcau

On the way to Forcau

Two parties to cave, the first enters at 12:30 (including Mike & Steve N. & François) and the second 15:30 (Bill +2), who meet François at top of the 5th pitch.  Steve E. climbs Peña Santa.

Descend six pitches: Entrance pitch 11m free-hanging, scramble down loose rocks to tighter passaage to pitch II, 8m.  Pitch III (estimates vary 8–15m).  Pitch IV 7m. Pitch V difficult to get on to, 37m free hanging – superb pitch.  Pitch VI a) 5m, b) free climb 4m, c) 25m top part climbing free hanging lower part out of waterfall.  Tight passage leads off from lower chamber – high narrow rift, very hard work.  Mike and Steve after puching this retire at 18:00.

Second party leapfrog first and on down.  Pitch VII (9m into streamway) required a bolt and this was a general excuse for a stop and a meal of dried apple, sponge fingers, cheese, sardines, hot sauerkraut etc.

From here on the supposedly open passage did not really open out – meandering stream passage, only 0.5m wide, with puddles and pools. After 100m character changes to very sharp projections on walls. After another 100m, at −160m, we stop for a sing-song La Rirette (Jeanneton prend sa faucille) whilst Pierre(?) explored ahead alone for another 200m to a duck where he turned back. (Editor’s note:  there were simply too many people in a tiny passage.) Returned to chamber below 7th pitch for coffee!

Meanwhile Gilbert, who had gone out with Steve & Mike, had not been able to get up the 6th pitch.  The 3 had arrived at that point at 19:00 and it was now 21:30; Mike having climbed the 5th pitch (37m) & had come back down to help Steve get up.  The rest of the party arrived at the bottom of the 6th pitch at about 9:40.  Mike then climbed the 5th pitch for the second time and after waiting there some time exited at 22:30 followed by Steve and Philippe at midnight.

Meanwhile back at the 6th pitch...
Gilbert had another attempt at climbing the 6th pitch – unsuccessful! We discussed the idea of leaving him there and returning with SCAL’s ladders.  At last he did ascend, slowly, and Bill followed, reaching the 5th pitch at about 23:00.  Here we all waited while Gilbert ascended. After 90 minutes, Bill ascended a little faster.  The next pitches were rather tiring as there was nobody below Bill to put weight on the ropes.  Whilst near the top of the 3rd pitch Bill experienced a fall of nearly 1m as the snagged rope slipped above and boulders crashed down! Meanwhile Gilbert was puking above.  Bill exits Forcau at 02:00 and the party rests and eats.  (The bread tasted so good in spite of, or even because of a slight dusting with powdered carbide!). Back at the camp-site at 04:00.

08.08 Rain.  Move back to Rales.  Martin stays behind at the Lakes.
09.08 Bill & Mike return to Bilbao via Cueva de Sangazo (correct name is Cueva de Lastrilla), near Castro Urdiales. Mike returns to UK.  Steve & Steve find a sea cave west of San Antolin and a small inland cave.
10.08 Steve N. drives to Los Lagos. Steve E and Bill swim at Barro beach – lunch in Marías José & Carmen’s garden. Steve, Bill, Ely, Conchita, Mari Luz –> Porrúa fiesta –> Rales and awaken Anne & Laurence!
11.08 Steve and Bill return to the lakes; François leaves for France.  See Victor (Jose Manuel Victorio) at midday. Steves & Bill have lunch and find cave and explore surface on road to Demues and hear of caves near Llano Con.  (Cueva del Agua – explored by Nottingham.)
12.08 Look for cave at Covadonga, Cueva de la Campana (sp?), but find another instead with waterworks.  Steve and Bill examine Cueva del Agua flood entrance (leads to pitch) and also find other small spring/cave further up the valley.  Victor Blanco (from Mexico) shows us entrance to Cueva el Osu.
13.08 On the way to Rales, Bill finds the real Cueva de la Campana; Martin and Bill find small resurgence at Santianes; walk up valley to Arroyo de Llovio and beyond to Cueva Negra.
14.08 Ramblers arrive.  Steve & Bill pick them up in Bilbao.  No sign of Penny Friedlander who apparently decides she’s not coming.
15.08 Fiesta.
16.08 Cares Gorge walk to Caín and back.
17.08 After 2 tortillas (dobles), Chris, Steve, and Bill explore 400–500m of Cueva Negra.  Stopped by 15m (est.) pitch.  Very like Lledales (see below).  Steve falls in pool of cowsh.  Returned through Cueva Tinganón. Steve Newton meanwhile finds resurgence at Niembru.
18.08 Fuente Dé to Carmameña via Bulnes walk.  Steve drives Chris, Bob, & Mike to Teléferico.  Martin walks towards Naranjo de Bulnes.  Steve E is ill.  Steve N & Bill find Cueva Peñado (sp?) resurgence near Arenas (path is 2.4km from bridge east of Arenas).
19.08 Day off on Barro beach and in Posada for lubrication. In Posada see photos of caves:  “El Tebellin” (Bricia), Jou Sanchez, El Conde, Jou Porquero, Jon Fria (30m, Niembro), Cebelin (see Cox 1973).
20.08 Fail to find/explore some of the above caves.
21.08 Rain. Festering.  Walk to [unreadable in log]
22.08 Sierra de Santianes exchange walk. Re-identify caves:

Old Negra = Tinganón system

Old Lledales = Cueva Negra

Old Jalcorneda = Cueva Lledales

Jalcorneda = impenetrable sink at cliff face

Fuente de San Juan at Santianes not investigated

23.08 Take ramblers to Amieva.  Bill, Martin, and Steve (and Chris?) eat an enormous tortilla in bar for 80 ptas.
24.08 Barro beach then –> Llanes for meal then Barro fiesta.  Mari Chielo pissed – declares her love and tries to swim in the sea at midnight.
25.08 Martin & Steve return to UK. Bill returns to Amieva.
26.08 Chris and Steve leave at 08:00 for Peña Santa.  Bill walks down Dobra Gorge.  Bob pukes.
27.08 Take ramblers to Rales via Cangas and Posada (conjuring in Café Moderno).
28.08 Up at 05:30 and leave Rales at 06:00. Arrive Bilbao at 11:00. Return to Pozo del Bosque picnic.
29.08 Collect Steve from Amieva, via Tornin fiesta. Posada until 03:30.
30.08 María del Mar arrives.  Hmmm.  For the whole of the weekend Bill is only conscious of the love birds fluttering around his head.  Marías Gloria & del Mar & Steve & Bill go to Llanes.  Bill wins 255 ptas at bingo in Acuario.  Ballandro (at Nueva?).
31.08 [No log entry.]
01.09 Wandered around Mestas, Riocaliente, Villa.
02.09 More Tinganón surveying. Letter from MdM.
03.09 Barro; not much sun.
04.09 Rain. Steve leaves.  Bill to Potes, Pineres, La Fuente: drove from Potes via La Hermida and up the recently tarmaced road (great improvement after 1973!) to Linares, Pineres, and La Fuente.  Wine only 2ptas a glass in La Fuente bar! Am informated of the following caves:  A major resurgence (hence La Fuente) which some say is enterable, others not; Trescuajara; Cueva La Nava (wet); Pico la cueva; Resperda; Cueva el Sevo; some of these may have been explored by a group from Madrid in 1974.  Left during torrential rain via Puentenansa.  Bar has dyeline of local cave with paintings.

At Celis, reports of many caves including Rengones.  Walk via dozens of depressions up to 30m deep without any reports of caves in them. Reach river Tanea.  Cueva de los Marranos at river level (explored by Manolocos de Madrid in 1973, 800m).  Farmer shows Bill the Cueva Toyu entrance (unexplored); possible through trip following Río Latarma.

05.09 Drove to Mestas and beyond. Where the road deteriorates en route to Riensena, on the left before the first hairpin bend, is a track through the wood.  It crosses the stream a couple of times and if one takes the path to the left near a 1–2m cascade one is within 30m of Cueva de las Inxanas (Chinchanas).  The entances are situated 20m up a steep undergrowth-covered bank and are in a limestone cliff face.  One goes 30m and continues.  Real cave, not just a rock shelter.
06-08.09 Waiting for MdM.  She arrives!
09.09 Return to Venta de Fresnedo valley to recce the six saddles and their cave systems.

Diagram of Caves of the Latarma valley, Venta de Fresnedo.
System 6 Riu Praucu Open resurgence entrance @498m
Sink @470m. System 5 (saddle @474m) El Seguedal Resurgence with stagnant pool @442m. Possibly impenetrable.
Sink @423m. System 4 (saddle @430m) La Huerta Resurgence cave with 2 big entrances @386m.  Grid 53289646. Length 130 m. Vertical Range 30m.  Torca del Joyu las Munecas Big entrance @625m 4.3 km long, Vertical Range 230m
Sink @ 381m. System 3 Comaria Open resurgence cave @370m explored for 50m. Main Sink @341m Flood bypass sink @350m. Cororigo System 2 (saddle @396m!).  Resurgence cave @270m. Grid 53379646. Length 204 m.  Vertical Range 22m.
Sumidero (Cueva) del Toyu @171m. Grid 53499643.  Length 1 km. Vertical Range 64m. Sistema del Toyu System 1 (saddle @209m) Manantial del Breno – impenetrable resurgence at river (Lamason) level @144m.
River resurgence into Rio Lamasón

Notes.  All the sinks are probably impenetrable and all the resurgences seem open cave entrances.  An exception to this rule is Toyu for which the contrary is true.  The Toyu system is susceptible to severe flooding and the water has been known to back up so high that the water flows over the saddle!

10.09Bill returns to UK via Bilbao ferry.  Exhaust pipe comes off 3 wheeler.

Other log details: Log includes diagram of Forcau pitches, diagram of Latarma valley, some addresses of French & Mexican cavers, and cumulative mileage/time chart driving through France and Spain. These pages have been scanned (from photocopies) and are available here.

Expeditions to the Picos de Europa and elsewhere since 1973.
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This page was last edited on 2023-03-09 by mfc.