Diving in Alonissos: Greece best-kept secret

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I’m delighted I can finally add Greece to my dive map, whereas it was actually my third trip. The first time I celebrated my 12th birthday near Athens and I taught myself how to read Greek. I guess it was the trip that made me fall in love with travelling and language learning. After exploring Crete in 2003 and becoming a scuba diver in 2009, I was eager to return to Greece to go scuba diving… but where? It was until I heard about diving in Alonissos in 2017.

Scuba diving in Greece was almost entirely forbidden until 2005 due to the risks towards its submerged archaeological patrimony. Rules became more flexible in 2006, explaining why the scuba diving industry is still very recent in Greece. While most people flock to Crete or the Cyclades, I got invited to explore a tiny island in the Northern Aegean Sea, eager to spread the word about their divers’ paradise: Alonissos, in the archipelago of the Sporades. When I found out about its marine protected area, one of the largest in Europe, and how the island was protected from mass tourism, I immediately started organising my trip.

Alonissos National Marine Park: a refuge for monk seaks and dolphins

Alonnisos National Marine Park was created in 1992 and was Greece’s first marine protected area. It covers 2,260 km2  and includes seven islands and 22 small islets.

The Park is divided into 3 zone A, B and C. Zone C, the core of the Park is around Piperi Island and has the highest level of protection. This is where the endangered monk seals (Monachus Monachus) live and breed.

They can sometimes be seen around Alonissos, but you will need to be extremely lucky as this is rare. With about 700 individuals left in the entire Mediterranean Sea, the monk seal is now the rarest seal on Earth. The colony of Alonissos National Marine Park counts between 55 to 60 individuals. It is sadly the biggest in the Mediterranean Sea. However, the fact they chose Alonissos National Park as their home shows the quality of the ecosystem.

MOm (Hellenic Society for the Study and Protection of the Monk seal) is the Greek non–profit organisation taking care of the protection of the Mediterranean monk seal. In 2016, after 25 years of efforts to preserve the species, the IUCN announced that the Mediterranean monk seal “stepped down” one category on the endangered species list, from “critically endangered” to “endangered”. Don’t hesitate to visit their information centre in the port of Patitiri.

Map Alonissos NAtional MArine Park

Please note that no tour is taking any visitor to see the monk seal colony on Piperi Island. This area is strictly forbidden to approach if not for authorised scientific research purposes.

Zone A is also strictly controlled: activities such as snorkelling tours or commercial fishing may be authorised if the management authority delivers a special permit, but scuba diving is strictly forbidden.

Zone B has the lowest level of protection which only includes a ban on wild camping and use of fire, with some areas where boat speed is limited. Still, in zone B, the port authority doesn’t allow scuba diving everywhere: for example, the entire north shore of Alonissos is prohibited for scuba divers.

While the monk seal is the star of Alonissos National Marine Park, the conservation effort also goes to cetaceans and the incredible biodiversity found around its islands. Four species of dolphins are regularly seen in the Park:

  • Striped dolphin (Stenella coeruleoalba)
  • Short-beaked common dolphin (Delphinus delphis)
  • Bottlenose dolphin (Tursiops truncatus)
  • Risso’s dolphin (Grampus griseus)

There have been sightings of Cuvier’s beaked whales (Ziphius Cavirostris) and even a few sperm whales (Physeter Macrocephalus)! 

The Northern Aegean Dolphin Project is a citizen science program conducted by MOm, aiming at recording encounters and behaviours such as social interactions of the different species of dolphins found in the Park. If you are interested in marine conservation, you can join and become a marine conservation research assistant for a week or even just a day.

A Greek island retreat in Alonissos

Relaxing holiday Alonissos Greece Paradise Hotel

Even the most hard-core adventurers sometimes need a break! Yes, even if I’m usually all about road trips and crossing entire countries to explore an extraordinary dive destination, I absolutely loved taking my 3h30 flight and my 1h30 ferry ride and just staying on the same island for a week.

I usually avoid European destinations at all costs in July and August. However, the promise of an out-of-the-beaten-track Greek Island, with crystal clear waters and authentic culture away from the crowds, definitely got me.

It was so funny how I quickly got used to my Alonissos routine. I woke up with sunrise at 6.30 am, prepared my Greek coffee at 8 am, and was scuba diving from 9.30 am to 1.30 pm. After lunch and relaxing by the pool, writing and editing pictures, I usually explored the island between 5 and 8 pm to enjoy cooler temperatures (the temperature was around 35°C around noon in August).

I could then enjoy a long Greek mezze dinner every night with my new friends at Triton Dive Centre! Alonissos is one of these scuba divers island paradises that will make you come back, again and again.

Top 5 dive sites of Alonissos

Scuba diving in Alonissos Greece

In 8 days, I dedicated one day at the beginning and one day in the end for flying between London Gatwick and Skiathos and taking the ferry between Skiathos and Alonissos. I had five days of scuba diving left because of the 24 hours of non-diving safety before the return flight. One diving day had to be cancelled because of the strong winds one morning, but I took the opportunity to join the afternoon snorkelling trip to Skopelos Island, which was just as awesome. In 4 days, I scuba dived eight times in seven different dive sites. Here is the selection of my five favourite dive sites during my 1-week holiday in Alonissos with are some of the best in Europe.

The Blue Cave

Thie blue cave is the dive site that amazed me the most in Alonissos, thanks to its diversity. Whether you are a beginner or an advanced scuba diver, if you like marine life or caverns, there is something for everyone at the Blue Cave.

The dive boat was stationed inside the Blue Cave, a large open sea cavern, but we started the dive by visiting the nearby wall on the right side. You can go deeper if you want, but it was in the 15-20 m zone that I found the most interesting marine species in the numerous cracks covered in sponges and cup coral: nudibranchs, scorpionfish, groupers.

In the second part of the dive, we were very shallow, between 5 and 10 m, to explore the different areas of the cave for some scenic views while doing our safety stop.

dive parameters: max depth 25,2 m – 54 minutes – water temperature 26°C

The Gorgonian Garden

I heard a lot of this dive site before diving there as it is one of the rare authorised dive sites in Alonissos where you can see so many beautiful red and yellow gorgonians. Unfortunately, because of the depth (you will need to be deep diver certified) and the currents, this dive site will be only for advanced divers.

As the boat needs to station in a sheltered creek, you need first to swim for about 25 m following the cliff on your left. When you see a pointed stripe of rock on your right, the red gorgonian wall starts at 35 m deep below the surface. When I was on the wall, I knew I would have only a few minutes of non-decompression time to take my pictures.

We started to ascend step by step by visiting the other side of the wall covered in yellow gorgonians at about 30 m deep. We then followed the cliff and did a long deep stop at 12/15 m before doing our final safety stop at 5 m.

We agreed with Martino, the instructor who was my buddy on this dive, that currents were moderates that day, but anyway, good air consumption management is the key when you have great depth and currents to manage.

dive parameters: max depth 41,4 m – 44 minutes – water temperature 26°C / 20°C at 30 m / 18°C at 40m

Agios Georgios South Reef

It was such a fun site to dive! Although you don’t need to go too deep on this site, the currents and different swim-through require scuba divers to perfectly control their buoyancy and know how to fin kick efficiently.

The dive site is made of two large pinnacles where you can find groupers, moray eels, scorpionfish and nudibranchs. At the beginning of the dive, we started by descending in a large chimney to a small sea cavern beautifully covered in sunset cup coral. Towards the end of the dive, this is where I saw the biggest moray eels of my diving trip in Alonissos.

dive parameters: max depth 26,7 m – 56 minutes – water temperature 26°C / 22°C at 25 m

Agios Petros Reef

I dived there twice, and each time we saw an adorable cuttlefish on the sandy bottom between the Posidonia seagrass patches. It’s also an excellent site for macro underwater photography with many nudibranchs and striped blennies that like to stay in front of the camera!

Towards the end of the dive site, you can find amphorae before making your way back to the boat! Unfortunately, they are not genuine ancient amphorae but copies. There are actually archaeological sites around Alonissos, but these are restricted and not allowed to scuba divers. However, these amphorae still make a fantastic subject to photograph!

Update 2021: It is now possible to scuba dive the ancient shipwreck of the Peristera!

1st dive parameters: max depth 16,3 m – 48 minutes – water temperature 26°C

2nd dive parameters: max depth 14,5 m – 71 minutes – water temperature 26°C

Mourtias North Reef

Mourtias Reef has a wall part between 20 and 30 m deep and a plateau part between 10 and 15 m deep. The plateau part was rich in nudibranchs feeding on sponges (spotted doris) or hydroids (flabellinas and hervias). In the middle of the wall, we saw three big groupers. Mourtias Reef is indeed famous for its large groupers.

Unfortunately, they were so shy that I couldn’t take any decent picture or video of them. Fair enough, I got it. Some marine animals hate my video torchlight. Only one solution, I need to upgrade my photo gear and get a strobe!

dive parameters: max depth 25,4 m – 43 minutes – water temperature 26°C / 25°C at 20 m

Who to go diving with in Alonissos?

The high scuba diving standards and the Greek hospitality of the Alonissos Triton Dive Center team were part of my relaxing scuba diving holiday in Alonissos.

After the first day of bringing down all my gear from my hotel to the dive centre, every morning, I just had to go to the boat directly in the port of Patitiri where my scuba babies would be ready and just waiting for me.

Triton Dive Center has a crew of 2 instructors, one divemaster and 3 to 4 divemasters in training, so you’ll have plenty of help and people around you during the dive showing you cool stuff underwater.

Suppose you are travelling without any scuba diving equipment. In that case, you’ll be glad to know they have brand new rental gear, including 5mm full suits with boots and adjustable fins (top of the comfort for Mediterranean waters), and the price of rental equipment is always included in the price of the dives.

They do a 2-tank dive trip in the morning, and another 2-tank trip in the afternoon, so you can choose to dive all day long or share your time between scuba diving and exploring the beautiful island of Alonissos!

How to go to Alonissos?

Arrival on Skiathos Island with Thomas Cook Airlines

Thanks to Skiathos Airport, you can fly direct from many places in Europe to the Sporades. Then from Skiathos, you take the catamaran “Flying Cat” or the speedboat “Flying Dolphin”, tickets start at 14€, you can buy your tickets directly from the travel agencies on the harbour.

Another alternative is to fly to Volos, the nearest airport on the continent, the ferry then will be just a bit more expensive, or to fly to Thessaloniki, but then the ferry is 2 hours and a half and costs about 40€ each way.

Check your ferry route with www.openseas.gr.

Where to stay on Alonissos?

During my stay in Alonissos, I had the opportunity to try two different hotels at different budgets around the Patitiri area.

The Atrium of Alonissos is a 4-star hotel, 15 minutes walking from Patitiri Harbour, which takes full advantage of its higher location. The hotel has several terraces at different levels and two swimming pools perfected oriented for sunrise in the morning. Bedrooms are large and have a minimalistic white style, and each has a balcony with a sea view. I loved their Greek coffee “machine” and the mini Alonissos pies (filo pastries with cheese or spinach) at breakfast while admiring the view. Double rooms start at 80€ in low season.

The Paradise Hotel is a 2-star hotel that has its entrance just above Patitiri Harbour and enjoys a perfect location on its poolside above the creeks between Patitiri and Roussoum. The rooms are more traditional and smaller, but they all get a beautiful view. My favourite thing was to enjoy one of the mini terraces along the stairs leading to the private creek where you can directly swim in the sea from the hotel. And by the way, try their watermelon feta cheese salad for lunch; it is to die for! Double rooms start at 55€ in low season.

You can also find budget-friendly pensions and apartments on booking.com from as little as 20€ the night for double occupancy.

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Many thanks to Triton Dive Center for inviting me to discover this incredible Greek island underwater and beyond. As always, all my views and opinions are my own and reflect honestly my experience there. Photo Credits: Alonissos National Marine Park map and pictures of monk seal and dolphins courtesy of MOm.


scuba diving in Alonissos Greece

Posted by Florine

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