Rondje Pampus

In 1296, the powerful Count Floris V attempted a desperate escape from the walls of Muiden Castle, only to be betrayed and brutally killed by his captors. Centuries later, the waters surrounding that same historic stronghold have transformed into the theatre for the Rondje Pampus, a swimming event that demands both tactical precision and endurance. As you plunge into the IJmeer, you are not merely crossing a lake; you are navigating the shadow of the Fort Pampus, an architectural marvel constructed between 1887 and 1895. Engineers of that era faced the daunting task of securing the entrance to Amsterdam, ultimately driving 3,852 piles—each eleven meters long—deep into the mud to support the fortress's heavy concrete and brick foundations. This legacy of engineering serves as your guide, as the 2,700-meter official KNZB competition course requires you to complete three distinct, tactical laps around the island.

The water and the landscape

While you focus on your stroke, the surrounding landscape tells a story of both nature and art. The IJmeer serves as a vital corridor for birdlife, and it is common to share these waters with scaups and tufted ducks that frequent the area. Look toward the horizon to spot the artificial islands of De Drost, Warenar, and Hooft; created in the 1960s as shelter dams, they carry the name of the 17th-century sheriff and poet P.C. Hooft. Near the Almere coast, you might catch a glimpse of the 'Polderland Garden of Love and Fire', a land art project by Daniel Libeskind that punctuates the shoreline. Closer to the fort itself, keep an eye out for the restored 'Mistklokhuisje', a historic fog bell house once vital for warning ships during low visibility. If you find yourself craving a different kind of technical challenge, the NK Open Water 2026 offers a distinct pacing later in the season. Whether you are aiming for the competitive 2,700-meter distance or participating in the 900-meter or 1,800-meter formats, the event remains a vital effort to study and protect the IJmeer ecosystem, with proceeds supporting research by Wageningen University & Research. The water here is unpredictable, shaped by the same winds that once forced merchant ships to lie 'voor Pampus' while waiting for the tide to clear the shallow passages.