Alonissos Marine Park Diving — Greece
The National Marine Park of Alonissos protects the critically endangered Mediterranean monk seal along with pristine Aegean reefs. Strict permit limits keep diver numbers low, and the underwater archaeology — including ancient shipwrecks — adds historical depth. The pine-forested Sporades islands are among Greece's loveliest.
- Score
- 66.6 / 100
- Country
- Greece
- Region
- Europe
- Area
- Sporades
- Nearest airport
- Skiathos (JSI) then ferry
- Visibility
- 15–30 m
- Water temperature
- 14–26 °C
- Max depth
- 40 m
- Current strength
- mild
- Dive types
- reef, wall, wreck, cave
- Best months
- May, June, July, August, September, October
- Minimum certification
- Open Water
- Access type
- boat
- Average 2-tank dive cost
- $95 USD
- Budget tier
- mid range
- Key species
- Mediterranean monk seal, dolphin, loggerhead turtle, grouper, Eleonora's falcon
- Google rating
- 4.7 (160 reviews)
- Top operators
- Alonissos Triton Dive Center, Ikion Diving
- Nearest hyperbaric chamber
- Athens Naval Hospital Chamber (~180 km)
SCORE
39.1550°N
23.8700°E
The National Marine Park of Alonissos protects the critically endangered Mediterranean monk seal along with pristine Aegean reefs. Strict permit limits keep diver numbers low, and the underwater archaeology — including ancient shipwrecks — adds historical depth. The pine-forested Sporades islands are among Greece's loveliest.
Europe's Largest Marine Protected Area
Score Breakdown
Click any score to see a detailed breakdown
Marine Life
72.0Species diversity, megafauna encounters, reef fish abundance, macro life, and endemic species.
Key Species
Dive Types
Traveling with Non-Divers?
Your non-diving travel companions will find plenty to enjoy topside while you're underwater. Here are some activities to consider.
Activities for Non-Divers
Nearby Cultural Sites
- Alonissos Old Town
- MOM Monk Seal Centre
Non-Diver Partner Score
Excellent for non-divers — they'll love it here.
Safety & Emergency
Dive Insurance
Dive insurance is essential. Standard travel insurance often excludes scuba diving. We recommend DAN (Divers Alert Network) for comprehensive dive accident coverage.
Learn More at DAN.orgHealth centre on island; air evacuation to Volos or Athens for serious cases
Top Operators
Alonissos Triton Dive Center
PADI
Ikion Diving
SSI
What your dive shop won't tell you
The minimum certification printed on a brochure is the legal floor, not the honest recommendation. Here's what we actually think you should bring to this site.
Below this we'd send you somewhere easier first.
“Intermediate minimum — deep profiles and variable viz.”
What will challenge you
- →Recreational limit of 40 m is reachable here (max depth 40 m). Gas planning and NDL tracking matter.
- →Cold water — 14°C at the coldest. Drysuit recommended; wetsuit divers will be genuinely cold past 30 minutes.
- →Overhead environment. Standard recreational training does not cover you past the entrance. People die here doing what they'd do on an open reef.
- →Wreck penetration requires Wreck specialty training at minimum, and often decompression planning. Don't improvise inside.
- →Nearest hyperbaric chamber is ~180 km away. Evacuation is slow. Dive conservative profiles and get DAN insurance before you fly.
- →Variable visibility
- →Deep profiles
What will surprise you
- →Permit-restricted access. Daily cap: 30 divers. Book 6+ months ahead through a licensed operator.
- →Alonissos Marine Park has more marine life variety than most divers expect
- →Local operators know spots the guidebooks miss
When to dive it
Every dive shop gives you this briefing at 7am. We just wrote it down. Tidal dependency: slight. Optimal window: First light to 11am for best visibility..
- Vizhigh
- Currentmild
- Crowdlight
- reef exploration
- photography
Best light and calmest conditions before afternoon wind picks up.
- Vizmoderate
- Currentmild
- Crowdmoderate
- drift diving
- second tank
Wind chop can reduce viz. Still diveable but morning is better.
Dive forecast
Realistic conditions by month. Viz ranges are what you should actually expect, not best-case marketing numbers. Confidence % is the share of days that match this profile historically.
| Month | Viz (m) | Temp (°C) | Current | Sea | Rain | Confidence | Highlights |
|---|---|---|---|---|---|---|---|
| Jan | 15–23 | 14 | Mild | Mod | Light | 70% | reef fish active, wreck visibility good, peak season crowds |
| Feb | 15–23 | 14 | Mild | Mod | Light | 70% | reef fish active, wreck visibility good, peak season crowds |
| Mar | 15–23 | 14 | Mild | Mod | Light | 70% | reef fish active, wreck visibility good, peak season crowds |
| Apr | 15–23 | 14 | Mild | Mod | Light | 70% | reef fish active, wreck visibility good |
| May | 27–30 | 26 | Mild | Calm | Dry | 70% | reef fish active, wreck visibility good |
| Jun | 27–30 | 26 | Mild | Calm | Dry | 70% | reef fish active, wreck visibility good |
| Jul | 27–30 | 26 | Mild | Calm | Dry | 70% | reef fish active, wreck visibility good |
| Aug | 27–30 | 26 | Mild | Calm | Dry | 70% | reef fish active, wreck visibility good |
| Sep | 27–30 | 26 | Mild | Calm | Dry | 70% | reef fish active, wreck visibility good |
| Oct | 15–23 | 14 | Mild | Mod | Light | 70% | reef fish active, wreck visibility good |
| Nov | 15–23 | 14 | Mild | Mod | Light | 70% | reef fish active, wreck visibility good |
| Dec | 15–23 | 14 | Mild | Mod | Light | 70% | reef fish active, wreck visibility good |
Photography brief
Subjects are only half the shot. A perfect macro site is useless in a three-knot drift, and a wide-angle dream is useless at 35 m with a murky ceiling. These are the conditions, not the hype.
Recommended kit
- →Dedicated video light for dark wreck interiors; don't rely on strobes alone
- →Two independent light sources minimum; video lights beat strobes in caverns
- →Cold-water housing — condensation is a real issue below 18°C, bring silica packs
What this site will teach you
The dives that made you a better diver are the ones that made you uncomfortable for the right reasons. Here's what this site will quietly train you for.
Deep diving comfort
advancedRegular dives past 30m build confidence at depth.
7-day trip, per person
Rough ranges anchored to existing regional data — not booking quotes. Land-based trip, standard breakdown.
Hostels, shore diving, cheap eats
- Flights (RT from US)
- $540–$660
- Accommodation / day
- $50–$100
- Diving / day
- $80–$100
- Food / day
- $30–$55
- Transfers + misc
- $50–$150
3-star hotels, standard boat ops, mix of restaurants
- Flights (RT from US)
- $810–$990
- Accommodation / day
- $120–$220
- Diving / day
- $100–$120
- Food / day
- $65–$110
- Transfers + misc
- $50–$150
Top resorts or liveaboards, premium operators
- Flights (RT from US)
- $1,450–$1,750
- Accommodation / day
- $260–$500
- Diving / day
- $120–$160
- Food / day
- $130–$250
- Transfers + misc
- $50–$150
Flights priced round-trip from a major US hub. Figures are per person on a shared room. Solo travelers add ~30% to accommodation.
Build a trip around it
Most divers fly across the world for one destination and don't realise another worth-it site is 90 minutes away. Here are the honest pairings.
- Zakynthos60.4Greece
Same country, easy to combine into one trip.
- Santorini Caldera59.4Greece
Same country, easy to combine into one trip.
- Crete67.5Greece
Same country, different dive character. Easy to combine in one trip without extra flights.
- Milos66.2Greece
Same country, different dive character. Easy to combine in one trip without extra flights.
- Gozo72.6Malta
Regional neighbour with a different dive type. Worth the extra flight if you want variety.
- Cabo de Palos71.1Spain
Regional neighbour with a different dive type. Worth the extra flight if you want variety.
Best dive types here