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.
On September 20 and 21, 2025, the Journées Européennes du Patrimoine (European Heritage Days) will be opening the doors to the unsuspected treasures of Paris and the Île-de-France region. In Val-d'Oise (95), head for Haute-Isle for a mineral immersion in the region's only troglodyte church, carved right into the cliff.
