NK Open Water — Amsterdam Gaasperplas

About the race

The water here is a deep, quiet mirror, broken only by the rhythmic pull of your stroke as you navigate the Gaasperplas. Beneath you, the lake hides a bustling ecosystem; if you glide through the shallower zones, keep an eye out for the freshwater crayfish scuttling over the silty bottom or schools of roach darting between the submerged vegetation. As you push forward, the silhouette of the Kekermetrobrug viaduct marks your orientation, a heavy, double-tracked industrial structure that has bisected the park landscape since the mid-seventies. Further along, the white domes of the Taibah Mosque rise above the tree line, a distinct architectural landmark known locally as the 'White Pearl of the Bijlmer'.

A park with a past. Swimming the course offers a unique vantage point of the Gaasperpark, which served as the grounds for the 1982 Floriade horticultural exposition. Traces of that grand event still linger in the park's deliberate layout, and on clear days, you can spot the remnants of the old planetarium structure near the shoreline. Not far from the water's edge, the landscape carries a more somber history; a grey poplar known as 'De Boom Die Alles Zag' stands as a living memorial to the 1992 El Al Flight 1862 crash, a site of quiet reflection for the surrounding community. For those looking to complete their season in these Dutch waters, the Rondje Pampus offers a contrasting experience in the open expanse of the IJmeer just a few weeks prior.

Race day logistics. The NK Open Water 2026, organized by the local club Zwemvereniging Het Y, brings a competitive edge to this suburban oasis. Held annually in September, the event typically sees water temperatures hovering around 17-18°C, making it a crisp test of endurance. The competition serves as a gathering point for swimmers ranging from club juniors to masters, often following the intensity of summer training cycles like those seen at the Marken Monnickendam event. As you round the final turn, the crystal-shaped pillars of the 1976 Kromwijkdreefbrug provide a final visual anchor before you reach the finish line, completing a course that weaves together modern Amsterdam infrastructure, horticultural history, and a rich, thriving aquatic environment.

Entry fees

• 250 m — 7 € · Open Water Challenge / performance swim
• 500 m — 7 € · Open Water Challenge / performance swim
• 1 km — 7 € · Open Water Challenge / performance swim (€ 12.00 per standard KNZB Het Y race; € 24.50 per individual ONK/NK championship race)
• 2 km — 12 € · Open Water Challenge / performance swim via pre-registration (€ 12.00 per standard KNZB Het Y race; € 24.50 per individual ONK/NK championship race)

Organizer

Zwemvereniging Het Y

Official site

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