The European Heritage Days return on September 20 and 21, 2025 with a promise: to make the heart of history beat to the rhythm of discovery. Île-de-France is transformed into a cultural playground, where curiosity and wonder become your best guides. Two days of wide-open doors to touch - sometimes literally - the soul of the most emblematic, most unusual and sometimes most secret places. Castles, museums, gardens, curiosities... Heritage can be experienced, listened to, smelled and enjoyed in a whole new way. It's the perfect opportunity to explore History with a capital H, in a sensory version that's freely accessible!
Did you know? There's an unusual troglodyte church in the Val d'Oise, just waiting to be discovered.
Did you know that in the Val d'Oise, the Church of the Annunciation at Haute-Isle is the only troglodyte church in the entire region? Carved directly into a chalk cliff and listed as a historic monument, it's an unusual nugget to discover. [Read more]
Why not dig a little deeper? Let's head for the Val-d'Oise (95), more precisely Haute-Isle, for a divine visit in both the literal and figurative sense: that of thetroglodyte church of the Annunciation. Carved out of the chalk rock between 1670 and 1673 at the request of Nicolas Dongois, the King's secretary, this church, the only one of its kind in Île-de-France, is the envy of the finest architectural gems. Entirely excavated from the cliff, only its masonry bell tower proudly protrudes from the hillside. At 26 metres long, 8 metres wide and 8 metres high, the nave is austerely mineral. Listed on the Inventaire Supplémentaire des Monuments Historiques since 1926, it continues to host services and ceremonies. As an added bonus, it's just a stone's throw from the troglodyte château of La Roche-Guyon!
### Visit the troglodyte church
Discover the troglodyte church of Haute-Isle, a remarkable historic site carved into the cliffs and the only church of its kind in the Paris region. It also offers a unique perspective on medieval architecture.
The Seine, architectural heritage
This program is part of the "La Seine, patrimoine architectural" event. On the occasion of the 2025 European Heritage Days, the villages of La Roche-Guyon, Haute-Isle and Vétheuil are joining forces to offer a unique and sensitive tour of the architectural heritage of the banks of the Seine.
Two days of rich programming, accessible to all, combining guided tours, exhibitions, concerts, lectures, artistic workshops and the opening of unusual places to discover the extent to which we owe the unique architecture of our villages to the Seine, and the extent to which it structures the landscape.
Dates and Opening Time
From September 20, 2025 to September 21, 2025
Location
Church of the Annunciation in Haute-Isle
144 Route de la Vallée
95780 Haute Isle
More information
Saturday, September 20, 2025 - 10:00 ⤏ 13:00, 14:00 ⤏ 19:00 Sunday, September 21, 2025 - 10:00 ⤏ 13:00, 14:00 ⤏ 19:00
Did you know? There's an unusual troglodyte church in the Val d'Oise, just waiting to be discovered.
