Rabo de Asno
Also known as: Donkey Tail Wall, Donkey's Tail Wall, Parede de Rabo de Asno, Parede Rabo de Asno
A red-and-purple gorgonian wall and swim-through cave in Peniche's outer Farilhões islets, entrance near 27m and floor near 32m.
Last updated September 2026
The dive
The descent starts at the surface, running alongside a rock wall dense with red and purple gorgonians that every source naming this site describes the same way. Following the wall down past roughly 27 metres brings you to the cave entrance, a hidden opening, not an obvious gash in the rock. Inside, the passage runs from one side of the islet to the other: a few metres in, the far exit is already visible ahead, and the gallery beyond holds a stillness divers describe as unusual, broken only by breathing and the bubbles collecting against the ceiling. Octopuses, scorpionfish and schools of seabream work the rock near the exit, and soft coral and European lobster line the walls of the cave itself. The floor, where four independent accounts converge, sits around 30 to 32 metres. The ascent runs back along the same gorgonian wall.
What makes it special
Rabo de Asno is the Farilhões' harder counterpoint to the sheltered wrecks and cave circuits back at Berlenga Grande: three independent sources place it in the outer, more exposed islet group, away from the main cluster, and the one operator that prices both routes charges more for it, EUR95 against EUR85 for the standard two-tank Berlengas trip. Divers come for the combination of a genuinely dense gorgonian wall and a through-cave at real depth, not for an easy dive: every source that discusses difficulty here ties it to the cave entrance's depth, not to current or navigation. That same depth is also where the certification advice contradicts itself. Two sources call Advanced Open Water sufficient for a "close to 30m" dive, but this site's own figures put the floor at 31 to 32 metres, past what AOW is meant to cover, and nothing found reconciles the two. Rabo de Asno is well corroborated as a dive worth the extra cost and the rougher crossing; it is not well corroborated as a dive with a settled answer on what certification actually covers the cave's floor.
Know before you go
The passage is a through-swim with a visible far exit, not a blind penetration, but it is still an overhead section at depth: stay with your guide until you can see daylight ahead, and carry a torch for the gorgonians and life along the walls, which sit outside ambient light. Expect the pricier, harder trip: the Farilhões sit at the archipelago's more exposed edge, and a 2010 account of this exact dive describes strong swell and wind forcing a sheltered gear-up inside the islet bay before dropping in. Crossing time is reported anywhere from about 25 to 45 minutes depending on the source, longer than the standard Berlenga run. Enriched air can extend your bottom time here if you already hold a nitrox specialty, but it is not something to assume the boat carries as a default. The BerlengasPass land-access fee applies to setting foot on Berlenga Grande; nothing found ties it to a boat dive at the Farilhões that never lands there.
Why Dive Rabo de Asno
What makes this dive site stand out.
- Gorgonian wall into a through-cave
A wall dense with red and purple gorgonians leads into a cave with an always-open far exit
- Entrance near 27m, floor near 32m
Four independent non-operator sources converge on this band within 2-3m
- Farilhões, not Berlengas proper
Sold as the outer islets' separate, pricier, harder day trip
- AOW called sufficient past its own ceiling
Two sources call Advanced Open Water enough at a depth past AOW's 30m limit
Depth & Profile
Location
39.4743°N, 9.5522°W
Conditions & difficulty
The Farilhões two-tank day trip that includes this site is priced at EUR95 per person by the operator that names Rabo de Asno as a regular stop, above the EUR85 standard Berlengas/Estelas two-tank trip; that same operator's own site does not confirm which sector this specific listing sits under.
Two independent sources call Advanced Open Water 'required' or 'essential' for this dive, but the site's own floor (31-32m) sits past AOW's 30m recreational ceiling; no source reconciles the gap. Plan to the depth your own training actually covers, not the trip's stated minimum.
Summary
The cave is a through-passage with a visible far exit, not a blind penetration, but an entrance past 27m plus a genuine overhead section meet the advanced threshold on depth alone.
Safety considerations
What can go wrong here, and what divers do about it. Conditions change - take the briefing from the operator on the day.
- Overhead: The wall descent leads into a cave that pierces the islet from side to side; the passage has a visible far exit, not a blind end, but it is still an overhead section at 27-32m.Carry a torch, stay with your guide, and confirm the far exit is in sight before committing to the passage.
- Depth: Two sources call Advanced Open Water sufficient for this dive while their own depth figures (31-32m) sit past AOW's 30m recreational ceiling; no source resolves the discrepancy.Dive to your own certification's depth limit, not the trip's stated minimum, and confirm the actual planned profile with your operator before booking.
- Surface and boat traffic: The Farilhões sit at the outer, more exposed edge of the archipelago; a 2010 trip report describes strong swell and wind forcing a sheltered gear-up inside the islet bay before the dive.Expect a rougher, longer crossing than the standard Berlengas day trip, and build slack into your schedule for a weather cancellation.
Marine Life
Rules and permits
- Conduct: no touching, no taking anything, no disturbing wildlife, no damage to the seabed, no litter.
Frequently Asked Questions
Do you need Advanced Open Water to dive Rabo de Asno?▾
Two independent accounts call Advanced Open Water required or essential for this dive, tying the requirement to its roughly 30m depth. But the site's own depth figures put the cave floor at 31-32m, past AOW's 30m recreational ceiling, and no source explains how that gap is meant to be covered. Treat the certification advice as unresolved, not settled, and plan your own profile to what your training actually covers.
Is Rabo de Asno part of the standard Berlengas day trip?▾
No. Three independent sources place it in the Farilhões, the outer, more exposed islet group sold as a separate day trip. The one operator that prices both routes charges EUR95 for the Farilhões two-tank trip against EUR85 for the standard Berlengas/Estelas trip, though that operator's own site does not itself state which price tab this specific listing falls under.
How deep is the cave at Rabo de Asno?▾
Four independent, non-operator sources plus the operator's own figure converge on an entrance around 27m and a floor around 30-32m. An older AI-generated search summary once suggested a shallower 25m, but that figure is not supported by any first-person account or operator page and is superseded by the converging depth reports.
Do you need a cave certification for the swim-through?▾
No source calls for one. The passage runs from one side of the islet to the other with the far exit visible from partway in, which is why one catalogue describes it as not requiring cave-specific training. It is still an overhead environment at depth, so a torch and a guide are standard practice regardless.
Does the BerlengasPass cover diving at the Farilhões?▾
Not as far as any source states. The BerlengasPass is a personal, non-transferable permit for setting foot on Berlenga Grande's land area, EUR3 per person. No source ties it to a boat dive at the Farilhões, which never lands on Berlenga Grande, though this reading is inferred from the pass's own land-access wording; the ICNF itself never states it outright.
How long is the boat crossing to Rabo de Asno?▾
Accounts disagree and neither figure is specific to the Farilhões run. A general Peniche destination page gives about 25 minutes; a 2020 trip report on this exact dive gives about 45 minutes. Since the Farilhões sit farther out than the standard Berlenga crossing, the longer figure is the safer planning assumption.
Can I use nitrox at Rabo de Asno?▾
One diver's account of this exact dive mentions enriched air as a way to extend bottom time past the no-decompression limit on air, but only for divers who have already completed a nitrox specialty course. It is not described as a standing option the operators hand out on request, so ask in advance and do not assume it is available.
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