Mermaid's Hole

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The most intriguing and challenging of all Doolin Green Holes. History of exploration of the longest Irish marine cave (and probably one of the longest marine caves in the world) is paved with great names of cave diving. It was late Ian Rolland who made first serious penetration– after 430m dive in 1987 he reached Pirates Paradise, dry chamber with fine straw gallery. Then Martyn Farr and Brian Judd continued the quest and the same year cave was already 700m long. Soon, 820m from the entrance and off the main route, Merrow’s Mirth – another dry chamber has been found. It was seemingly choked at the end but according to Martyn and Brian it may repay further investigation. Main route continued under the water and in 1991 Martyn reached 900m followed by very low section barely 25cm high. That seemed like a bitter end but in two years time Brian Judd passed the squeeze and extended exploration limits to 935 m meeting junction and another low section.

Underwater entrance to Mermaid's hole is situated at -10m under obvious ledge visible at low tide.

07.09.2008 Diver: Artur Kozlowski

Third attempt to get to Merrow's Mirth chamber this year. Third time lucky!!! I passed low section 700m in and after some confusion on last junction I surfaced in Merrow's Mirth! It's impressive rift, 6-7m high, 2m wide max. I have crawled over the boulders and found Martyn's old reel there, still with ~100m of orange line on it. Chamber seems to be choked at the end with the boulders but just before I surfaced I saw passage on my right hand side, going underwater parallel to dry rift. I followed it for 5m to some restriction. I approach my thirds so I couldn't even think about passing it but passage seemed to continue after. However there was no flow in this branch of cave - all flow was coming from north lead on the last junction.

17.09.2008 Diver: Artur Kozlowski

I got in at 7am at the peak of high tide with 2x12l steel and 2x11l alu all sidemounted. I got to Martyn's limit from 1991 900m from the entrance in 1h20min. I have passed 5m squeeze , at this stage vis was none, I got to my thirds and I was already scared to death...not enough courage to go on, maybe next time... I'm pleased anyway, I didn't really think that squeeze would be passable. Merrow's Mirth chamber revisited on the way out, no final conclusions.

21.09.2008 Diver: Artur Kozlowski

On Sunday morning I passed squeeze at 900m and after another 30m of low passage I reached Brian's massive reel left 15 years ago at the final junction ( for that 35m extension he used some kind of 2mm blue electric cable and after 20m or so kind of 3-4mm yellow cable). Brian described right hand side lead (NE) as 'looks too low' and left hand side lead (W/NW) as 'low but may be possible'. As the tide already turned and I could see bit of flow coming out of NE lead the choice could be only one. I attached my 50m reel to Brian's one and started squeezing into NE passage, 1m wide and 30-35cm high. Bottom was composed of soft silt and mud so I could dig out my way through at the expense of zero vis behind me - but I belayed my line very carefully expecting no vis on return. Horribly low passage was meandering along NNE/NE axis for about 20m and then I got a bit of space, 0.5 high. Around 35m I dug out through another low section and it opened again to 0.5m 1m wide all the time. I run out of 50m line, I looked ahead, 1 m in front of me low arch was connecting to much bigger passage 1.5m by 2m wide extending SW and NE. I assessed the situation and left my reel in place just to swim out into bigger passage. Spacious passage seemed to continue with tidal flow coming out from NE branch. When I turned the dive I had still 160 and 180 bars in my 12ls ( I dropped one 11l alu by the first air bell (Piscean Bell)and second one at the junction with Merrow's Mirth ) so there's still a lot of potential in this 4 tanks configuration and I find it comfortable enough there. I did survey of extension on the way back, dept at the end 5.9m, 1h after 4m high tide. I forgot to note down turning time but I reached your 900m limit in 57min from the entrance and I was back in 2h and 5min. Exit through mine and Brian's extensions was in 10cm to none vis. End of the line 985m.

24.09.2008 Diver: Artur Kozlowski

Sea conditions were fine, I reached the end of my line in 1h05min. I had 100m reel with me unfortunately after 20m of progress passage became very low - 30cm. I could see it going like that for at least another 10m. Floor was made of compacted cobbles and there were some bigger loose stones as well. So all you can do is remove the loose ones and try to squeeze, no chances to make the way bigger by digging. I had ridiculously plenty of air due to new gas management strategy - when I reached EOL 985m from the entrance I had 190B in each of 12l tanks, depth 5.5m. Nevertheless I decided to turn as the passage became narrow as well - finding space to turn your body was next to impossible. First 200m of my return trip was in 5cm vis. End of the line 1014m.

29.12.2008 Diver: Artur Kozlowski

Dive to EOL 1014m. Some line corrections and alternations on the way in. Passage at the end extremely tight, no more than 0.3m. All of my 4 tanks were under pumped so after 8m of progress or so I turned the dive. Passage at the end is only 1m wide so there's no place to turn your body. Going backward I got stuck once so I promised myself that next time I would excavate it a little bit more before entering. On the way out I investigated side passages going out from recent extensions. Some of them might prove interesting especially the one on last junction. EOL 1022m

30.12.2008 Diver: Artur Kozlowski

More gas in tanks. I delayed my entry to half an hour after high tide so I could have strong ebb current at EOL - for good vis and fast clearing of excavated mud. On Monday I didn't see properly what was ahead so I couldn't tell whether passage was going or not. When I reached EOL after 1h 17m emptying tide was already strong and I could see that way on was not opening. I made my way through another couple of meters but without proper excavation progress is not safe nor even possible. For another 5m I could see the passage to be only ~25cm high but flow is still coming out of it, so is a siren song... EOL 1025m.