The 10 km is the marathon of open-water swimming — the distance raced at the Olympic Games and the ultimate goal for endurance swimmers. Ten continuous kilometres in a lake, river or sea is a profound physical and mental challenge that few attempt and fewer master. This page collects every upcoming 10 km open-water swim across Central and Eastern Europe, with dates, locations, organisers and direct online-registration links.
Marathon swimming rewards relentless pacing, disciplined fuelling and the resilience to keep stroking for hours. It often requires separate qualification and serious preparation, but the achievement is unmatched in the swimming world. Set in the region's most spectacular natural waters, a 10 km swim is the pinnacle of the open-water calendar.
Choose the 10 km swim that matches your experience and sign up in a few clicks. Every listing carries the start date, location, organiser and a secure registration link.
The calendar refreshes daily, so you always see the current 10 km open-water swims in Ukraine, Poland, Romania and neighbouring countries. Prepare thoroughly and let Startlek help you find your marathon swim.