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Grotta dell'olio, Mondello
Italy · cave · beginner
6–12 mbeginnerOWboat entry
Grotta dell'olio, Mondello
The one cave on the Capo Gallo promontory whose entrance is underwater, plus the tunnel field in front of it.
Max depth6–12 m
Required levelbeginner
Entry typeboat
Visibilitynot sourced
The dive
The Grotta dell'Olio sits at the locality of Malpasso, on the Monte Gallo promontory that closes the bay of Mondello to the west, about 4 km from Mondello itself. The Sicilian regional geosite record lists it inside the Riserva Naturale Orientata di Capo Gallo, and Balarm makes the point that gives the site its reason to exist as a dive: of the promontory's many caves, this is the only one whose entrance is submerged, so a visit means getting in the water. Divers describe it as a half-drowned chamber at the foot of the rock wall, at the head of a small inlet, with a sandy floor at 6 to 7 m.
The managing authority for the marine protected area, which publishes the site as one of its fifteen numbered diving itineraries, gives it 8 to 12 m, calls the difficulty low, classes it as a multilevel dive in Zone B, and rates visibility as excellent. Palermo dive centres put the working range a little deeper, up to 18 m, if you include the wall outside; the conservative figure is used here. In front of the cave mouth runs a field of narrow passages, small arches and tunnels through the rock, encrusted with cup corals, and it is these "cunicoli" rather than the chamber itself that most of the local operators sell the dive on. One Palermo centre is explicit that the passages under the cunicoli are to be done only behind an experienced guide.
Being shallow, shaded and overhung, the cave holds shade-loving life: pale sponges, crustaceans and molluscs wedged in the cracks, small lobsters, and shoals of salema, saddled sea bream and corb that come further inshore than the depth would suggest. Occurrence records logged around the pin add octopus, moray, damselfish, ornate wrasse, Mediterranean parrotfish, scorpionfish and fan mussel.
The name is not explained by any source with confidence. Balarm offers three readings and endorses none: the oily look of the light on the water surface seen from below, an oily film that appears on the sea in summer as algae rot, or an unverified story about small boats using the cave to stash barrels of oil.
- The only cave on the Capo Gallo promontory with a submerged entrance
- Chamber with a sandy floor at 6 to 7 m, shallow enough for long bottom times
- Field of narrow tunnels and small rock arches in front of the cave mouth
- Cup-coral encrustation and shade-dwelling sponges, crustaceans and molluscs
- Published by the marine protected area as one of its fifteen diving itineraries
Please note before you go
- Overhead environment: the cave entrance is submerged and the chamber is enclosed
- The tunnel and passage field in front of the cave is an overhead too; one Palermo operator states the cunicoli are to be swum only behind an experienced guide
- Silt on the sandy floor of the chamber is easy to stir up in an enclosed space
Access & rules
Mandatory requirementsGetting there
By boat, as a Zone B itinerary of the Capo Gallo — Isola delle Femmine marine protected area. Palermo centres run it from the marinas on the Sferracavallo and Addaura side of the promontory; one long-standing Palermo school sells it jointly with the neighbouring cunicoli as a single dive. Balarm reports that in summer the entrance itself is commonly reached by snorkellers and by non-motorised craft, and that at low water the mouth admits a large canoe.
Operator
Access to the site runs through a local operator.
Restrictions
Inside the Capo Gallo — Isola delle Femmine marine protected area, in Zone B. The authority's own rules allow guided dives that it regulates and caps in number, through authorised dive centres, and independent dives only with a permit issued by the managing body. Balarm states the cave is visitable only by booking and with the marine protected area's authorisation. Mooring by pleasure craft in Zones B and C is allowed only on the authority's own buoy fields, with an access permit obtained online.
Rules and permits
The Capo Gallo — Isola delle Femmine marine protected area was established by ministerial decree of 24 July 2002 and covers the coast from the Capo Gallo promontory to Isola delle Femmine, in the municipalities of Palermo and Isola delle Femmine. Zone A, where diving with or without breathing apparatus is banned outright except under authorised scientific programmes, covers the north-western and north-eastern sectors of Isola delle Femmine and the stretch of sea west of Capo Gallo between la Puntazza and the Capo Gallo lighthouse. This dive is published by the authority as a Zone B itinerary and so falls outside the ban, but a neighbouring cave on the same promontory, the Grotta della Mazzara, was closed to recreational divers when it fell inside Zone A. The land above is the Riserva Naturale Orientata di Capo Gallo, and the cave is registered as a geosite within it.
Season
No source identifies a diving season for this site, so no months are claimed. One seasonal detail is on record and it cuts the other way: Balarm reports that in summer a slick from decaying algae can appear on the sea surface here, and offers that as one of the unproven explanations for the cave's name.
Conditions
Visibilitynot sourced
Currentnot sourced
Surgenot sourced
WaterSalt water
Depth range6–12 m
Environmentcave
Coralnot sourced
Crowdsnot sourced
The marine protected area's itinerary sheet rates visibility here as excellent and the profile as multilevel, which matches a shallow, sheltered inlet on the seaward face of the promontory. No source consulted reports current or surge as a normal feature.
On current: No source consulted reports current as a factor at this site, so none is claimed. The figures that do disagree are the depths: the marine protected area's own itinerary sheet gives 8/12 m, while Palermo dive centres give 10/18 m for the wider route outside the cave, and both describe a sandy floor inside the chamber at 6 to 7 m. The shallower, authority-published range is the one recorded here. Note also that two of the operator descriptions are word-for-word the same text, so they are one source rather than two agreeing.
Questions & answers
How deep is the Grotta dell'Olio?
The marine protected area's own itinerary sheet gives 8 to 12 m and calls it a multilevel dive. Palermo dive centres quote 10 to 18 m if the wall outside the cave is included, and both they and the authority describe the sandy floor inside the chamber sitting at 6 to 7 m. The shallower authority figure is the one used here.
Where exactly is the Grotta dell'Olio and how do you get there?
It is at the locality of Malpasso on the Monte Gallo promontory, about 4 km from Mondello, on the seaward face of the mountain at the head of a small inlet. Dive centres reach it by boat from the marinas either side of the promontory and normally combine it with the tunnel field in front of it. Balarm reports that in summer the entrance itself is also reached by snorkellers and by canoe.
Do I need a permit to dive the Grotta dell'Olio?
Yes. The site is a Zone B itinerary of the Capo Gallo — Isola delle Femmine marine protected area. The authority allows guided dives that it regulates and limits in number, run through authorised dive centres, and allows independent dives only with its own authorisation. Balarm states the cave can be visited only by booking and with the marine protected area's permission. Pleasure craft also need an online mooring permit for the authority's buoy fields.
Is the Grotta dell'Olio suitable for beginners?
The marine protected area rates the difficulty as low and one Palermo centre lists Scuba Diver and Junior Open Water as its minimum certification, calling the dive easy. That said, the cave entrance is submerged and the passages in front of it are an overhead environment; the same centre states plainly that the cunicoli should only be swum behind an experienced guide. Take a torch.
Can you snorkel the Grotta dell'Olio?
To an extent, yes. Balarm records that plenty of summer visitors reach the cave entrance with mask and fins alone, and that at low water the mouth is wide enough for a large canoe to pass through. Going inside the chamber and into the tunnel field is a different proposition and needs scuba, a light and a guide, plus the marine protected area's authorisation.
What will I see at the Grotta dell'Olio?
Because the site is shaded and overhung it holds shade-loving life: pale sponges, crustaceans and molluscs in the cracks, and the rock around the tunnels is encrusted with cup corals. Local operators name small lobsters and shoals of salema, saddled sea bream and corb. Occurrence records logged around the pin also include octopus, moray, damselfish, ornate wrasse, Mediterranean parrotfish, scorpionfish and the fan mussel Pinna nobilis.
Why is it called the Grotta dell'Olio?
Nobody is sure, and no source claims to be. Balarm sets out three explanations without endorsing any: the oily quality of the light on the water surface when you look up at it from inside, an oily film that forms on the sea here in summer as algae decay, or an unverified tradition that small boats once used the cave to store barrels of oil.
Is diving allowed everywhere around Capo Gallo?
No. Zone A of the marine protected area bans diving with or without breathing apparatus except under authorised scientific programmes, and it covers the sea west of Capo Gallo between la Puntazza and the lighthouse as well as the north-western and north-eastern sectors of Isola delle Femmine. A neighbouring cave on the same promontory, the Grotta della Mazzara, was closed to recreational divers for exactly that reason. The Grotta dell'Olio is published by the authority as a Zone B itinerary and is open under the Zone B rules.
Life recorded at Grotta dell'olio, Mondello
55 species within 2.32 km · OBISOctopus vulgarisrare · 3 recordsTursiops truncatusrare · 1 records
Chromis chromisoccasional · 19 records
Paracentrotus lividusoccasional · 9 records
Sarpa salpaoccasional · 7 records
Velella velellaoccasional · 7 records
All 55 species recorded in this area
| Species | How often | Records |
|---|---|---|
| Chromis chromis | occasional | 19 |
| Paracentrotus lividus | occasional | 9 |
| Sarpa salpa | occasional | 7 |
| Velella velella | occasional | 7 |
| Pachygrapsus marmoratus | occasional | 5 |
| Pinna nobilis | occasional | 5 |
| Serranus scriba | rare | 4 |
| Scorpaena maderensis | rare | 3 |
| Thalassoma pavo | rare | 3 |
| Diplodus sargus | rare | 3 |
| Diplodus vulgaris | rare | 3 |
| Pelagia noctiluca | rare | 3 |
| Octopus vulgaris | rare | 3 |
| Symphodus tinca | rare | 3 |
| Coris julis | rare | 2 |
| Ophioderma longicaudum | rare | 2 |
| Tripterygion tripteronotum | rare | 2 |
| Sparisoma cretense | rare | 2 |
| Ligia italica | rare | 2 |
| Clibanarius erythropus | rare | 2 |
| Aplidium tabarquensis | rare | 2 |
| Elysia timida | rare | 1 |
| Thuridilla hopei | rare | 1 |
| Haliotis tuberculata | rare | 1 |
| Rapana venosa | rare | 1 |
| Patella caerulea | rare | 1 |
| Patella rustica | rare | 1 |
| Phorcus richardi | rare | 1 |
| Sparus aurata | rare | 1 |
| Sarcotragus spinosulus | rare | 1 |
| Lutjanus sebae | rare | 1 |
| Symphodus roissali | rare | 1 |
| Steromphala divaricata | rare | 1 |
| Rhyssoplax olivacea | rare | 1 |
| Oblada melanurus | rare | 1 |
| Eriphia verrucosa | rare | 1 |
| Xantho poressa | rare | 1 |
| Percnon gibbesi | rare | 1 |
| Coscinasterias tenuispina | rare | 1 |
| Holothuria (Platyperona) sanctori | rare | 1 |
| Echinaster (Echinaster) sepositus | rare | 1 |
| Muraena helena | rare | 1 |
| Synodus saurus | rare | 1 |
| Parablennius gattorugine | rare | 1 |
| Parablennius sanguinolentus | rare | 1 |
| Salaria pavo | rare | 1 |
| Caranx crysos | rare | 1 |
| Seriola fasciata | rare | 1 |
| Gobius paganellus | rare | 1 |
| Mullus surmuletus | rare | 1 |
| Lithognathus mormyrus | rare | 1 |
| Scorpaena porcus | rare | 1 |
| Cotylorhiza tuberculata | rare | 1 |
| Tursiops truncatus | rare | 1 |
| Pisania striata | rare | 1 |
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SiciliaBeen here? Log it.
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