Dodecanese Islands Guide: Kos, Patmos, and Symi
The Dodecanese Islands stretch across the southeastern Aegean Sea, north of Rhodes, forming a Greek archipelago of more than a dozen islands. From Kos's ancient Asklepion and Castle of the Knights to the Monastery of St John on Patmos, from Symi's neoclassical harbour houses to Kalymnos's sponge-diving heritage, each island carries its own distinct character. Nisyros's volcanic crater and Leros's Italian-era architecture round out the picture.
## What Should You See in Kos?
One of Kos Town's most recognisable structures is the castle built by the Knights of Rhodes during the medieval period; standing guard over the harbour entrance, it remains one of the island's defining landmarks. Just beside it, in the town's main square, stands a giant plane tree traditionally associated with Hippocrates; while its exact age isn't established with certainty, the legend reinforces the island's long connection to the history of medicine. A few kilometres southwest of the town centre lies the Asklepion, a terraced sanctuary that served as a centre of healing in antiquity, where Hippocrates is believed to have taught. Spread across three terraces, the site is the island's most significant archaeological complex for anyone interested in its ancient medical tradition.
## Why Is Patmos So Significant?
Patmos holds a special place in Christian history; it is where Saint John is believed to have received the Book of Revelation, inside a cave. Known as the Cave of the Apocalypse, this sacred site remains one of the island's most visited points and continues to function as a place of worship. Perched on the hill above, the Monastery of St John the Theologian is notable for its fortress-like walls and rich collection of manuscripts; together with the cave, it has been inscribed on the UNESCO World Heritage List since 1999. The narrow lanes and whitewashed houses of Chora form a tightly knit settlement around the monastery.
## What Does Symi's Harbour Reveal?
The view that greets visitors approaching Symi's harbour is a tightly packed row of pastel-coloured neoclassical mansions; these houses date largely from the 19th century, when the island prospered from the sponge trade. Rising in tiers around the natural amphitheatre of the harbour, the buildings form one of the most recognisable waterfront silhouettes in the Dodecanese. Inland, religious sites such as the Panormitis Monastery sit alongside small coves; despite its modest size, Symi's architectural character makes it one of the region's notable stops.
## What Do Kalymnos, Leros, and Nisyros Offer?
Kalymnos has long been associated with a tradition of sponge diving, and the island's limestone cliffs also host a network of routes that draw international climbers. Leros stands out for its World War II-era fortifications and the Italian-built town of Lakki, whose architecture reflects the rationalist style of that period. Nisyros contains the caldera of a dormant volcano; the Stefanos crater is a spot visitors can descend into on foot, getting a close look at the volcanic terrain. Together, the three islands introduce a lesser-known side of the Dodecanese beyond Kos, Patmos, and Symi.
FAQ
How do you get to the Dodecanese Islands?
The most common way to reach the Dodecanese Islands is by ferry; regular routes connect the islands from Piraeus or via Rhodes, while Kos and Rhodes also have direct flight connections. Smaller islands such as Patmos, Symi, Kalymnos, Leros, and Nisyros are typically reached by ferries departing from Rhodes or Kos, and sometimes by short inter-island boat connections. Ferry frequency increases during the summer months, while winter schedules can be considerably reduced, so checking current timetables before travelling is advisable.
When is the best time to visit the Dodecanese Islands?
Spring (April to June) and early autumn (September to October) are generally considered the most favourable periods for visiting the Dodecanese Islands, as temperatures are comfortable for swimming and walking and crowds are noticeably thinner than in summer. July and August bring the hottest weather and the heaviest tourist traffic, so booking ferries and accommodation well in advance is advisable during those months. In winter, many facilities close and inter-island ferry services are significantly reduced, which can make travel planning considerably more difficult.