Greek Seas

For us Greeks, the essence of our heritage, our survival and our cherished summers are the Greek seas. It’s a shared habitat with remarkable species like the ancient Mediterranean inhabitant, the Caretta sea turtle, which finds ideal nesting grounds in our country, and the majestic sperm whale, which navigates submarine canyons up to 5,100 meters deep.

The Greek coastline offers a wide range of beaches and destinations to suit all tastes, in addition to underwater routes and sea voyages. In addition, Greek fishermen carry on centuries-old traditions that weave the tapestry of our cultural heritage.

The main seas of Greece are:

  1. Aegean Sea: Located between the Greek peninsula on the west and Asia Minor on the east, the Aegean Sea covers an area of approximately 83,000 square miles. It is connected to the Black Sea through the straits of the Dardanelles, the Sea of Marmara, and the Bosporus. The Aegean Sea is home to numerous islands, including Crete, which marks its southern boundary.
  2. Ionian Sea: This sea is a large bay of the Adriatic Sea, spanning the distance between Italy on its western shore and Greece on its eastern shore. The Ionian Sea includes the Greek Ionian islands, such as Corfu, Ithaca, Kefalonia, Kythira, Lefkada, Paxi, and Zakynthos.
  3. The South Sea of Crete, also known as the Libyan Sea, is part of the Mediterranean Sea. It is of great geographical complexity and hosts a rich biodiversity, including unique marine flora and fauna.

These seas are home to a rich variety of marine life, including fish, dolphins, whales, and sea turtles. They also have a long history of human activity, including shipping, fishing, and coastal urban development. The Greek seas are known for their beautiful landscapes, clear blue waters, and numerous islands, making them popular destinations for tourists and sailors alike.

map of the seas of greece

The Coastline and the Islands of Greece

The coastline of Greece is 13,676 km (8,498 miles), about 30% of the total Mediterranean coastline (46,000 km).

The coastal zone (up to 50 km from the sea) is home to 85% of the population, 80% of industry, 90% of tourism, a large percentage of farming activity and almost the whole of the fishing and fish-farming industries.

The country features around 6000 islands and islets, but only 227 of them are inhabited. They are the most popular Greek destinations, especially in summer. Big or tiny, green or arid, ideal for cosmopolitan or relaxing vacations, one thing is for sure: all have the requirements and facilities to offer you memorable and safe vacations!

Water Temperature of the Greek Seas

Typically, water temperatures in the Aegean and the Ionian Sea range from about 60 to 77 °F (16 to 25 °C). During the summer, surface water temperatures can rise to about 22 to 25 °C, while during the winter they often drop to 11 to 15 °C.

At depths greater than 350 meters, the water temperature remains constant throughout the year at around 12 to 13 degrees Celsius.

It is important to recognize, however, that these temperatures are subject to variations influenced by factors such as prevailing weather conditions, specific geographic locations, and seasonal changes. In particular, water temperatures near the coast can vary significantly from these general averages, especially after heavy rainfall, near estuaries, or after prolonged periods of strong offshore winds.

Impact of Greek Seas on the Economy

Greece’s coastal areas are crucial to the country’s economy, primarily through shipping, fisheries and aquaculture, tourism, and energy.

Shipping is a key industry, with Greece having the largest merchant fleet in the world in terms of tonnage. In 2018, the value of the shipping sector was $21.9 billion, reaching $23.7 billion when related businesses are included. It provided employment for approximately 392,000 people, representing 14% of Greece’s workforce. The Greek merchant navy managed a deadweight tonnage (DWT) of 834,649,089 tons on 5,626 Greek-owned vessels in 2018.

The fisheries and aquaculture sector is another important economic contributor, especially in coastal regions. In 2018, Greek fish production amounted to 0.2 million tons, with a value of $794.4 million. Aquaculture accounted for 80% of this value, while the rest came from wild fisheries. The sector employed 24,825 people in 2018, with Greece investing 5 million euros in fisheries services.

Tourism is vital, especially in coastal destinations such as Halkidiki, Western Messinia, Mani and Pelion. These areas attract tourists from around the world for their natural beauty, historical sites, luxury accommodations, and water sports.

Finally, Greece’s coastal regions hold potential for energy production, particularly natural gas reserves. Greece’s claimed Exclusive Economic Zone (EEZ) includes several islands in the Aegean and Ionian seas. Plans are underway for an undersea pipeline to transport gas from the Leviathan reservoir to Europe via Greece, promoting an energy alliance between Greece, Cyprus and Israel.

The Aegean Sea

Oia in Santorini island in the Aegean Sea
Oia in Santorini island, Greece

The Aegean Sea is an elongated embayment of the Mediterranean Sea located between Europe and Asia, specifically between the Balkans and Anatolia. It covers an area of approximately 215,000 km² and is connected to the Marmara Sea, which in turn connects to the Black Sea, by the straits of the Dardanelles and the Bosporus. The Aegean Sea is home to over 200 inhabited islands, including Crete and Rhodes, which bound it on its southern periphery.

Aegean Sea reaches a maximum depth of 3.544 m (11.627 ft) to the east of Crete and west of Karpathos.

The Aegean Sea is known for its rich biodiversity. It hosts 12 marine mammal species that are at risk and supports extensive areas of priority protected habitats, including Posidonia seagrass beds and Coralligene reefs. The marine ecosystems of the region also support hundreds of fish species and thousands of invertebrate species. Several species of dolphins, whales, sea turtles, and sharks, as well as the endangered Mediterranean monk seals, can be found in the eastern Aegean alone.

Historically, the Aegean Sea was home to the Minoan civilization, which flourished in Crete from c. 2700 to c. 1450 BC, and the Mycenean civilization (c. 1600–1100 BC), which arose in the Peloponnese. Both of these civilizations are covered by the general term Aegean Civilization.

According to Greek Mythology, the Aegean Sea took its name after Aegeus or Aegeas, the father of Theseus, who threw himself and died in the sea because he thought that his son was dead.

Today, the Aegean Sea is a popular tourist destination, with islands like Mykonos and Santorini being among the top tourist destinations in the world. These islands offer beautiful beaches, vibrant nightlife, delicious food, and a rich history and culture. Other popular destinations in the Aegean Sea include the medieval center of Rhodes town, the ruins of Ephesus in Turkey, and the island of Crete, which offers a variety of outdoor activities such as canoeing and hiking.

Aegean Islands

The Aegean Islands are divided into seven distinct groups, extending from north to south:

  • the Northeastern Aegean Islands: Thassos, Samothrace, Lesvos, Chios, Samos, Limnos, Ikaria, Agios Efstratios, Psara, Fournoi, Oinousses
  • Evia
  • the Sporades: Skiathos, Skopelos, Alonissos
  • the Cyclades: Naxos, Andros, Paros, Paros, Tinos, Milos, Kea, Amorgos, Ios, Mykonos, Mykonos, Syros, Santorini, Serifos, Sifnos, Sikinos, Anafi, Kimolos, Folegandros, Schinoussa, Koufonisia, Delos
  • the Saronic Islands: Aegina, Hydra, Poros, Spetses
  • the Dodecanese Islands: Rhodes, Karpathos, Kos, Kalymnos, Astypalaea, Kasos, Tilos, Tilos, Symi, Leros, Nisyros, Patmos, Halki, Lipsi, Kastellorizo, Telendos
  • Crete

The Aegean Islands are characterized by their hot Mediterranean climate with warm summers and mild winters.

These islands are celebrated for their stunning natural beauty and unique architecture, which has been a highlight for countless visitors, illuminating their vacations and creating unforgettable experiences.

Offering a spectrum of activities, the Aegean Islands cater to diverse interests ranging from boating excursions, walking tours, hiking adventures and cultural explorations. They are also renowned for their unique local culinary delights and recipes. The islands serve as an ideal retreat for beach lovers, with their golden sands inviting visitors to indulge in leisurely day-long stays.

Historically, the Aegean Islands have witnessed significant events, including their occupation by Italy during the Italo-Turkish War in 1912. Subsequently, islands such as the Dodecanese, Rhodes and Kastellorizo were annexed until 1947. These islands were finally ceded to Greece after the peace treaty of 1947, marking an important chapter in their rich historical narrative.

Ionian Sea

assos village in kefalonia island in the ionian sea
Assos village in Kefalonia, Ionian Sea

The Ionian Sea is the western maritime border of Greece and it includes the Ionian Islands, a group consisting of Corfu, Paxoi, Kefalonia, Zakynthos, Lefkada and Ithaca.

The Ionian Sea is also an important ecological zone. It boasts the Calypso Deep, the deepest point in the Mediterranean at 5,109 meters (16,762 feet), and supports a diverse marine ecosystem, including monk seals, whales, dolphins, and various species of fish and mollusks.

Historically, the Ionian Sea has been an important battleground, most notably as the site of the Battle of Actium in 31 BC, a decisive naval confrontation between Octavian and Mark Antony. Its mythological associations are equally profound, particularly with Ulysses, the legendary Greek hero from the island of Ithaca.

As a tourist destination, the Ionian Sea offers an enchanting blend of natural beauty and cultural appeal. Each island has its own unique charm, from the stunning beaches of Lefkada and Kefalonia to the quaint, picturesque villages of Corfu and Zakynthos. The crystal clear waters of the sea make it an ideal place for snorkeling and diving, providing an intimate view of the diverse marine life.

For those planning a visit, the optimal times are the tranquil spring months of April and May or the quiet period of September and October. These months offer a perfect balance of pleasant weather and reduced tourist activity. However, the Ionian Sea remains a year-round destination with its captivating landscapes and rich cultural tapestry.

Biodiversity of the Seas of Greece

The Greek seas, especially the Aegean Sea, stand out in the global context for their extraordinary biodiversity. Although they represent only 0.8% of the world’s seas, they are part of the Mediterranean Sea, which is home to a remarkable 7% of the world’s marine species.

The Aegean and the Ionian Sea are home to 12 endangered marine mammal species and extensive areas of ecologically important habitats, including Posidonia seagrass beds and Coralligene reefs.

In terms of marine fauna, the Greek seas are home to a unique diversity, including various species of dolphins, whales, sea turtles, sharks and especially the endangered Mediterranean monk seal. These species are mainly found in the eastern Aegean. However, the region is not without its challenges, facing an influx of at least 242 alien species into its territorial waters.

The biodiversity of the Greek seas is currently facing significant threats, mainly from climate change and invasive alien species. The eastern Mediterranean, which includes the Greek seas, has experienced a significant increase in sea surface temperatures over the last two decades. This ongoing warming trend poses risks of salinization and water mass stabilization, with potential negative impacts on marine biodiversity.

Endangered Species

Greece’s marine ecosystems are characterized by their rich biodiversity, but many species in these waters are critically threatened by habitat degradation, overfishing and climate change. Among the most threatened species in Greek seas are

  1. Mediterranean monk seal: Recognized as one of the world’s most endangered marine mammals, the Mediterranean monk seal is the subject of extensive scientific research in Greece, where its breeding populations are monitored year-round.
  2. Dolphins and whales: The Greek seas are home to several endangered species of dolphins and whales. These include the fin whale, known for having the largest brain of any animal, the sperm whale and the elusive Cuvier’s beaked whale.
  3. Sea Turtles: In particular, the Caretta Caretta turtle, a species endemic to the Greek seas, faces daunting survival odds, with estimates suggesting that only one in 1,000 hatchlings survive to adulthood.
  4. Sharks: Several shark species, including the critically endangered Angel Shark and the Gulper Shark, face significant risks in these waters. The Angel Shark, in particular, has experienced a drastic population decline, leading to its listing as Critically Endangered by the IUCN.
  5. Fish Species: A number of fish species are also endangered in the Greek seas, such as the Adriatic sturgeon, the Aegean minnow, Alosa vistonica and the dusky grouper.

In response to these challenges, organizations such as WWF Greece, Archipelagos and iSea are actively involved in conservation efforts. These initiatives include the monitoring of marine activities, the formulation of precise management and conservation strategies, and research to better understand and address the specific needs of each threatened species.

Alonissos and Northern Sporades National Marine Park

Established as the first marine park in Greece, the Alonissos and Northern Sporades National Marine Park has the distinction of being the largest marine protected area in Europe, covering a vast area of over 2,260 square kilometers. Strategically located in the Northern Sporades region of the northern Aegean Sea, the park includes the island of Alonissos, six smaller islands (namely Peristera, Kyra Panagia, Gioura, Psathoura, Piperi and Skantzoura) and an additional 22 uninhabited islets and rocks.

Established with the aim of protecting, conserving and managing the region’s natural heritage and valuable national natural resources, the park is recognized for its significant biological, ecological, aesthetic, scientific, geomorphological and educational values. It serves as a critical habitat for the Mediterranean seal Monachus monachus, currently listed as the most endangered marine mammal. In addition, the park is a sanctuary for a number of other terrestrial and marine species, encompassing a diverse range of flora and fauna.

Greece and the Sea: An Inseparable Bond

boat sailing in the greek seas

To broadly outline Greece’s identity, it is essential to include the sea among its defining elements – ancient culture, philosophy, mythology, art, and its European character. The geographical and historical fabric of Greece is intricately woven with the maritime element.

A glance at a map reveals the crucial role of the sea in shaping our nation. Our ancient civilization thrived along coastlines and islands stretching from Asia Minor to mainland Greece. Our far-flung colonies, scattered across the Mediterranean and the Black Sea, were a testament to our maritime prowess. The trade routes were also predominantly nautical.

Naval power was a cornerstone of Alexander the Great’s campaigns, and Byzantine power peaked with its naval dominance. The Revolution of 1821 drew its formidable strength from our island fleets. Even our national flag, a symbol of modern Greece, originally had two versions – one for land and one for sea, eventually adopting the latter. What other nation has so vividly captured the unique significance of the sea in its identity?

Today, our relationship with the sea remains crucial, especially in times of economic crisis. Tourism and shipping remain resilient sectors, contributing significantly to economic recovery. Greek ships, a dominant force in global maritime trade for decades, continue to traverse the oceans. The majority of our cities and population are coastal, living in tandem with the sea. “Our blood is salty. The brine is in our boats and ships, in our homes and on our skin,” say our fishermen, who live their lives at sea and long for it even on land.

It is impossible to imagine Greece without the sea. It would be a completely different country, and we Greeks would be ‘others’. The sea offers a unique aesthetic perception of reality, beckoning us to adventure and challenge. It demands constant activity and innovation, urging us to reshape our lives and forge our future. Every Greek sailor carries a trace of Ulysses in his heart, and every Greek who has read the Odyssey repeatedly feels the grandeur and adventure of life echoed in the whispers and songs of the sea.

The islands and islets of the Aegean, Ionian and our other seas, together with the coasts of the mainland, form the richest geographical mosaic in the world. Each island is a unique tile of beauty, with its own aesthetic, where the sea plays with the land. The rocky barrenness of our islands has been transformed into maritime wealth thanks to the ingenuity and determination of our islanders. Even our smallest islands have given rise to shipowners who navigate every corner of the globe.

As you travel the world, you appreciate the local beauty and ingenuity of nature and people. But this only heightens the appreciation for the beauty of the Greek seas and intensifies the desire to embrace the Aegean, to be on every island simultaneously, to savor the unique ecstasy offered by every bay, every playful wave and every rock.

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