Sunrise Swim Portoroz powered by Alpen Adria Swim Cup

First light spreads across the sheltered waters before the waterfront of Portorož wakes up. The Sunrise Swim Portoroz powered by Alpen Adria Swim Cup takes place in the open sea off Portorož, along the Slovenian coast, organized by Alpen Adria Swim Cup in the calm morning hours of June. Swimmers enter a semi-enclosed marine basin spanning 19 square kilometres in the northern reaches of the Adriatic Sea. It is an exceptionally gentle stretch of coast for open water racing, with an even seabed that remains shallow throughout, holding depths mostly between 15 and 20 metres. Stepping into the water at dawn means gliding across a mirror-calm bay protected from outer sea swells. The morning sun lifts gradually behind the coastal hills, lighting the clear, sheltered sea as you stroke away from the sand into the open bay.

The Portorož shore: roses, salt and the Bernardin point

The name Portorož derives from Santa Maria delle Rose, the patron saint of a former church in the settlement. Portorož had a monastery of Saint Laurence, where the Benedictines healed rheumatic illnesses, ascites and other diseases with concentrated saltwater and saline mud. Bernardin, in the western part of Portorož, was a shipyard for smaller vessels before the hotel complexes were built. The monastery tied to Saint Bernardino's Church at Bernardin was closed in 1806, and in 1830 the Austrian military converted it into a fortress to guard the Bay of Piran. On the hill of Crocebianca (Beli Križ) above Portorož there is a viewpoint over the Portorož bay.

Rt Madona and the underwater Triglav reef

The underwater promontory of Rt Madona marks the deepest spot in the entire Gulf of Trieste. Known locally as the underwater Triglav, this submarine abyss reaches a depth of 37.25 metres, yet the surrounding waters are remarkably benign, protected as a 13-hectare marine natural monument where the seabed shelves progressively from the shoreline. Below the surface, solid bedrock and tumbled boulders slope downward toward a gentle sedimentary floor. These rocks are draped in thick marine canopies of brown and green algae, including Cystoseira, Sargassum, Dictyota, Halimeda, and Padina.

Sečovlje Salina and the Dragonja river mouth

The Slovenian shoreline extends for just 46.6 kilometres, forming the compact Slovene Riviera that runs south toward the village of Sečovlje. From Piran toward Cape Seča, the coast rises in steep, layered cliffs formed of flysch sandstone and marl that drop directly into the water. These crumbling sedimentary cliffs give way at the southern corner of the bay to broad coastal wetlands and alluvial flats. Here, the Dragonja river flows out of the Šavrin Hills to meet the sea, laying down the river sediment that created the Sečovlje Salina Nature Park. Salt production in these shallow coastal shallows is ancient, first recorded at the Rižana Assembly in 804 and later governed by the historic Piran Statute of 1274. Today, the vast pans of quiet water mirror the morning sky.

Kanal svetega Jerneja and traditional wooden boatyards

The Kanal svetega Jerneja is a sheltered tidal inlet that receives no freshwater river tributaries. Fed exclusively by rainwater and seawater drawn in from the Gulf of Piran, the canal creates a unique brackish environment where specialized marine plants and estuarine fish thrive. During the rule of the Venetian Republic, the canal was a bustling mercantile hub where five massive wooden warehouses stored white sea salt ready to be loaded onto Venetian cargo fleets. At the mouth of the channel where it spills into the bay, a shallow lagoon preserves Istria's last traditional wooden shipyard. For generations, shipwrights maintained local wooden craft by intentionally grounding them in the soft mud of the lagoon at low tide to scrub the exposed hull, before letting the incoming tide right the boat so they could roll it over onto the opposite side.

Zambratija Bay and the Savudrija headland

Beyond the Dragonja river mouth, the shoreline shifts character dramatically, turning into a steep, rugged coast of pale limestone heading toward Cape Savudrija. In the shallow waters of Zambratija Bay, about eight kilometres down the coast from Portorož, a local fisherman in 2008 spotted the outline of an ancient wooden structure resting in the sediment just 150 metres from shore. Archaeologists revealed it to be a Late Bronze Age vessel dating from between the 12th and 10th century BCE, recognized as the oldest sewn boat discovered anywhere in the Mediterranean. Measuring 6.7 by 1.6 metres in its preserved state and reconstructed to an original length of 9 metres, the craft served as the archetypal blueprint for all prehistoric sewn vessels across the sea.

Ancient builders hand-stitched the hull using elm wood, flexible fir laths, and vegetal wadding, sealing every seam with pitch to keep it watertight against the waves. On the rocky tip of the cape stands the Savudrija lighthouse, the oldest operational beacon along the Adriatic Sea, raised from local limestone blocks in 1818. Originally designed to burn coal—a technological first for marine lighting—its 29-metre stone tower was later heightened by ten metres in the late 19th century. Today it casts three white flashes every fifteen seconds across a range of 30 nautical miles, tied to romantic lore of Count Metternich, who reportedly constructed the coastal tower for a Croatian noblewoman he met at a Viennese ball.

Fiesa Bay cliffs and the coastal brackish lakes

The coastline forms a sweeping bend at Fiesa Bay. Tucked directly behind the beach are two quiet lakes formed in the early 20th century inside the hollows of an abandoned brickworks clay pit. The smaller pit holds water down to a depth of 6.5 metres. The larger lake sits just 20 metres from the sea, dropping to 9 metres deep and absorbing saltwater seepage from the shore. This makes it the only brackish lake in Slovenia, an extraordinary coastal refuge just paces from the bay. When you finish your morning swim in the Gulf of Piran, the water is already warming beneath the sun, offering a calm, clear swim along a coastline steeped in natural history.