OncoSwim

Late May waters along the Costa Brava typically hover near 18-19°C, a temperature that demands consistent movement to maintain core warmth during the 30-kilometer haul. Swimmers starting at dawn from the beach in L'Estartit encounter the influence of the Ter river, whose discharge into the Mediterranean at 'la Gola' creates subtle shifts in salinity and density that seasoned competitors learn to navigate. While surface conditions are generally manageable, the open-sea nature of the route requires awareness of the currents swirling around the islands; these are not tidal in the oceanic sense but are heavily shaped by wind-driven surface flow and the seabed topography of the continental shelf.

Marine corridors and rugged shores

Crossing the Medes Islands marine reserve offers a rare glimpse into a protected ecosystem where underwater visibility often peaks, allowing swimmers to observe rock formations extending from the Montgrí Massif. This limestone range plunges sharply into the sea, providing a wild backdrop that persists until the approach to the Formigues Islands. Historically, these waters required constant vigilance; the coastline is dotted with defensive structures built to counter 18th-century pirate raids, which remain visible landmarks from the water. Those seeking to compare this long-distance effort with shorter, localized challenges might consider the Cala Montgó Swim Crossing or the 55th Illes Medes-Estartit Crossing, both of which test stamina in nearby waters.

Logistics of an epic crossing

The 30-kilometer event is a logistical operation, not a standard race, requiring teams of four to manage rotation strategies from an accompanying support boat. The registration fees, ranging from 750 to 1,500 EUR, reflect the necessity of these vessels for safety and navigation across such an expansive, non-linear course. After the start at 7:00 AM, the journey concludes at En Calau Beach in Calella de Palafrugell, where the Solidary Mile participants join the finish-line atmosphere in the late afternoon. Swimmers receive an official cap, a certificate of completion, and the satisfaction of contributing to the oncology projects supported by the foundation behind the event, which has grown significantly since its inception, raising nearly 100,000 EUR in previous cycles.