The Ionian Sea, where the Ionian Islands such as Kefalonia, Lefkada, Corfu or Zakynthos can be find, is located off the western coast of mainland Greece and stretching along the eastern coastline of Italy. It is bordering the Adriatic Sea to the northwest, the Mediterranean Sea to the south, and the Greek mainland and the Peloponnese to the east.
The Ionian Sea, or as the Greek people name it as Ιόνιο Πέλαγος (Ionio Pelagos) is one of the most beloved seas in Greece for its clear waters, beautiful varied coastline and interesting marine life. The area of the Ionian Sea has extremely rich cultural heritage, because this region is filled by very important trade routes since thousands of years, with sailors of Venetians, Greeks and other nations of the Mediterranean regions.

It’s an important information that the Ionian Sea is not just belong to the Ionian Islands, but also this sea is which borders several great holiday destinations of the Greek mainland, such as Igoumenitsa, Syvota, Parga, Loutsa, Preveza, etc!
Geography and Topography of Ionian Sea
The Ionian Sea spans approximately 169 000 square kilometers (65 000 square miles), stretching between Italy, Greece and Albania. It is connecting to the Adriatic Sea in the northwest, and has an average depth of about 1400 meters (4,600 feet). The deepest point of the Ionian Sea reaches approximately 5,109 m (16,762 ft) in the Calypso Deep, making it the deepest place in the Mediterranean world!
The coastline of the Ionian Sea is diverse, which is often characterized by dramatic cliffs and pebble beaches, surrounded by lush green landscapes. The underwater topography of the sea is equally varied with underwater mountains, cliffs and caves, and of course many deep trenches that create unique marine environments ideal for diverse marine species and popular among divers and underwater explorers.

Under the Ionian Sea giant tectonic plates come together, which is the reason that this region area has earthquakes quite often. The earthquake of 1953, which destroyed many buildings in Kefalonia, Ithaca and Zakynthos, was also due for the tectonic plates. The strict building regulations of the Ionian Islands require to build earthquake resistant houses, following strict guidelines.
The Ionian Islands
The Ionian Islands, often called the “Heptanese” or “Seven Islands,” are a group of Greek islands which are located in the Ionian Sea. Although we mention it as the Seven Islands, this group includes much more than just seven, with many smaller islets and islands dotting this region. Corfu (Κέρκυρα) or Kerkyra is the northernmost and one of the largest Ionian Islands. Corfu is extremely popular in tourism since decades, because the island is famous for its lush landscapes, old Venetian architectures and famous historical sites. It offers beautiful, mostly sandy beaches and an amazing mix of Greek, Venetian, French and British cultural influences.

Paxos and Antipaxos are located near Corfu in the Ionian Sea. These islands are famous for their secluded beaches and tranquil atmospheres, making ideal conditions for those seeking a peaceful retreat. The visitors of Antipaxos appreciate its white sandy beaches and clear waters, which are really postcard-like! Local boat trips from Corfu or Parga visit Paxos and Antipaxos islands daily during summer months, but Paxos is connecting the Greek mainland by ferries as well (Igoumenitsa).
We like Lefkada in Greece very much for its stunning blue and white beaches, including Porto Katsiki beach, Egremni beach and Kathisma beach. This is a very special island in the Ionian Sea, because Lefkada is connecting to the mainland by a pontoon bridge, and you don’t need to travel by a ferry! This island attracts visitors not just with its exceptional coastlines, but also with its vibrant seaside towns such as Lefkada town, Nidri or Agios Nikitas. Lefkada has the best surf spots in the area of Ionian Islands, because the local windsurfing and kitesurfing spots (in Vasiliki and in Agios Ioannis) have extremely good conditions for these actitivies.

Ithaca (Ithaki) is small, but charming island, which considered as the home of Odysseus in Homer’s epic, The Odyssey. If you are looking for a peaceful place in the Ionian Islands, this place will attract you, and its mythical significance and hidden coves with emerald coloured waters are also recommended.
One of our favourite island in the heart of the Ionian Sea is the largest one: Kefalonia (Κεφαλονιά), or Cephalonia. This is not just the largest, but the highest of the Ionian Islands with the height of 1628 meters. Due for its big size Kefalonia has very diverse landscapes and beaches, even there are unique natural phenonemons! But altough this is the largest member of the Ionian Islands, when we compare the islands of Greece, Kefalonia is the 6th in size. There are Greek Islands in the Aegean region, which are bigger, such as Crete, Evia, Rhodes, Lesvos or Chios.
The most famous spots of the island are Myrtos Beach with its dramatic cliffs, the beautiful Melissani Cave Lake, the sacred monasteries. We must mention the rich local wine culture, especially its native Robola wine!

Zakynthos (Zante) is one of the most known Greek island in the world, due to its most famous place, the Navagio beach (Shipwreck). This beach is among the most photographed in Greece with its vertical walls and extremely blue waters. The island is also an important nesting place for loggerhead sea turtles (Caretta Caretta), and has a lot of natural protected areas.
Kythira is uniqe among the islands of the Ionian Islands, because it is located slightly apart from the other Ionian Islands. Kythira has a unique blend of Ionian and Aegean element, but it beloved also for its secluded beaches, Byzantine churches and peaceful atmospheres. Even the island of Kythira belong to the Ionian Islands, but it is not belong to the Ionian Sea! This interesting piece of Greece is situated further away in the south. The distance from Zakynthos is approx 230 kilometers, so there are no ferries from other Ionian Islands to Kythira.

History and Cultural Significance of the Ionian Sea
The Ionian Sea has played a significant role both in ancient and modern history. The region served as a key area of trade and cultural exchange for thousands of years. During antiquity, the Ionian Sea was part of important trade routes used by the Greeks, Phoenicians and Romans. Ancient settlements flourished along the coastlines and islands, leading to the spread of Hellenic culture and art.

Mythology and legend are also deeply embedded in the Ionian Sea. The most famous tale associated with the region is that of Odysseus and his journey home to Ithaca in Homer’s The Odyssey. This epic journey through the Ionian waters has added a deeper layer of mystique to the area, drawing literature lovers and historians to explore the places that inspired such legendary tales.
In later centuries, the islands and coastal areas around the Ionian Sea became important centers during the Byzantine, Venetian and Ottoman eras. Venetians left a long lasting influence almost everywhere in the region, especially on the architectures. Many of the islands retain Venetian-style buildings and fortifications on the top of some hills. The islands were also the only part of Greece that never came under long Ottoman control, thanks to their Venetian protectorate status.
Marine Life and Ecology of Ionian Sea
The locals who live in the area of the Ionian Sea, are proud for the rich marine biodiversity of the sea. The sea’s varied depths, underwater topography and nutrient-rich waters support a wide range of marine life, making it an attractive destination snorkeling, diving, and also for fishing tours. The Ionian Sea is home to some dolphin species, including the common dolphin, bottlenose dolphin, and striped dolphin. The region is a part of the Ionian Dolphin Project, a conservation initiative aimed at studying and protecting these dolphin populations.

The loggerhead turtle is an endangered species that nests on the sandy beaches of Zakynthos and Kefalonia. Zakynthos’ Laganas Bay is a protected area designated as part of Greece’s National Marine Park to ensure the protection of these turtles’ nesting grounds. The Mediterranean monk seal, one of the world’s rarest marine mammals, is occasionally spotted in the caves and remote coastlines of the Ionian Islands. Efforts to protect and monitor this endangered species are ongoing, as the Ionian Sea provides an important habitat for its survival.
The Ionian Sea supports a diverse range of fishes, including seabreams, groupers, red mullets, swordfishes, octopuses, moray eels, and squids are common sightings. The rich marine flora is due for the seagrass meadows of the coastal areas, which play important role in maintaining the health of the local ecosystems and provide basic habitat for many kind of marine species.
Activities and Attractions in the Ionian Sea
The Ionian Sea’s is perfect for numerous water activities. The calm and warm waters and scenic coastlines make the Ionian Sea ideal for sailing. Numerous charter companies operate in the ports of the region, and sailors can explore the islands at their own pace, anchoring in secluded coves and hidden beaches.
The clear visibility and diverse underwater environments make the Ionian Sea one of Greece’s best diving and snorkeling destinations. Visitors can explore the reefs, underwater caves and in some cases historic shipwrecks. Notable dive sites include the Blue Caves of Zakynthos, the Keri Caves also in Zakynthos, and the sea caves around the coastline of Kefalonia.

The calm sea conditions make the Ionian Sea an excellent place for kayaking and paddleboarding, particularly along the sheltered coastlines of the islands where visitors can explore hidden coves and rocky coastlines. The best places for kayaking and for SUP mostly the east coasts of the Ionian Islands, where the sea is usually calmer comparing with the west.
For biggest fans of best beaches is very important, that the Ionian Islands offer some of Greece’s most beautiful beaches! We must mention iconic Navagio Beach on Zakyntho with its famous shipwreck, to the dramatic white cliffs and blue waters of Myrtos Beach on Kefalonia, the extreme blue beaches of Lefkada, the Ionian Islands are ideal for sunbathing, swimming, and enjoying the sea.

On daily boat tours you a chance to spot dolphins, sea turtles, and in very rare cases, but occasionally monk seals. These tours are particularly popular around Zakynthos, Kefalonia, and Ithaca, where dolphin and turtle sightings are frequent.
Conservation
As other places in the world, the Ionian Sea faces many environmental challenges. Most common are the overfishing, the pollution, and the effects of climate change have impacted marine ecosystems in recent decades. Conservation organizations and marine parks, such as the National Marine Park of Zakynthos, are actively working to protect vulnerable species like the loggerhead sea turtles and monk seals and to preserve the region’s biodiversity.
Final thoughts about IOnian Sea
The Ionian Sea is a region of beautiful places and ecological significance in Greece with a lof ot unique properties. Its crystal-clear waters and idyllic Ionian Islands make it a paradise for travelers seeking impressive natural beauties and adventures both!