Nature Festival in L'Isle-Adam 2026, a free must-see in Val-d'Oise

Nature Festival 2026 comes to La Rosière Park in L'Isle-Adam, Val-d'Oise, this Saturday, May 23, 2026. On the program: nature stalls, biodiversity discovery, and activities for children, all free of charge.

The Fête de la Nature marks its 20th anniversary this year, and L'Isle-Adam in the Val-d'Oise (95) is once again taking part in this nationwide celebration. Join us on Saturday, May 23, 2026 at the Parc de la Rosière for a day of discovery that is free and dedicated to local biodiversity, with stalls, activities and workshops for young and old.

La Rosière is a little pocket of nature in L'Isle-Adam. Spanning 11 hectares along the Oise, this biodiversity site links the river to the forest of L'Isle-Adam through a mosaic of remarkable habitats: ponds, hay meadows, hedgerows, orchards, pike-spawning grounds, and a beekeeping area. You’ll even find Ouessant sheep, ditch goats, and Highland cattle taking part in eco-grazing. Suffice to say, the scenery immediately sets the tone.

For this 2026 edition of the Fête de la Nature, the Isle-Adam Festival Committee is ready to roll with creative workshops for children, a fun, hands-on way to explore nature and the environment. In previous years, the various stands offered opportunities to discover the wildlife and flora of wetlands with the IASEF, delve into the fascinating world of hedgerows and insects, or watch the pike spawning at the fishery with the Val-d’Oise Federation for Fishing and the Protection of the Aquatic Environment. Visitors could also try macro-nature photography, get up close to beehives with a local beekeeper, or take home bulbs distributed by the town gardeners. A wonderful way to leave with full hands (and pockets).

What stands out here is how the place and the event fit each other so well. La Rosière isn’t just a leafy municipal park; it’s a living laboratory where nature has reclaimed a former plot once used for intensive farming. About sixty bird species have been recorded here, including the grey heron, the common buzzard, and the kingfisher. On days like this, the volunteers and local associations on site help the public view this discreet yet very real ecosystem in a new light.

The event is part of the national program of the Fête de la Nature, which this year runs from May 20 to 25, 2026 across France, centered on the International Day of Biodiversity on May 22. In Île-de-France, the ARB îdF has been coordinating nature activities across the Paris region for more than 15 years.

This is a day out we especially recommend for families with kids, curious urban-nature lovers, and anyone looking for a pleasant Sunday stroll less than an hour from Paris. The Parc de la Rosière in L'Isle-Adam sits beside the Oise river and not far from Parc de Cassan with its famous Chinese pavilion—a great detour to fit into the same day. The entry is gratuite, with no reservation required.

For more information, visit the town of L'Isle-Adam's website and view the full program at fetedelanature.com.

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