Heritage Days 2025 at the Pavillon Royal de la Muette in Saint-Germain-en-Laye (78)

The 42nd European Heritage Days kick off on September 20 and 21, 2025! This year's not-to-be-missed event returns to the Yvelines, to highlight the richness of our historical heritage by opening the doors of emblematic sites such as museums, institutions and châteaux. In Saint-Germain-en-Laye, let yourself be seduced by original guided tours revealing the best-kept secrets of this royal town. What's on the program? A weekend of unexpected discoveries and revelations, immersing you in the rich heritage of this region steeped in history.

Journées du Patrimoine 2025: a must-see program of visits in Yvelines (78)
There's plenty to do for the Journées du Patrimoine 2025 in the Yvelines! On Saturday September 20 and Sunday September 21, 2025, we're off to the many castles and museums of the 78 region to open their doors to you for guided tours, workshops and family fun. [Read more]

For the Journées du Patrimoine 2025, don't miss the exceptional opening of the Pavillon Royal de la Muette on Saturday, September 20! This Petit Trianon, nestled in the heart of the Saint-Germain-en-Laye forest in the Yvelines, has been masterfully restored by Emmanuel Basse and Benoît d'Halluin, two patrons of the arts with a passion for history. After four years of work, this jewel of French heritage, once Louis XV's hunting lodge, has been restored to its former glory. Built by Ange-Jacques Gabriel in 1767 on the remains of a François 1er château, the pavilion has been given a new lease of life in keeping with 18th-century codes.

• To be read
• This week's best deals in Paris and Île-de-France, March 30 to April 5, 2026

Programme of the Journées du Patrimoine 2025 at the Pavillon Royal de la Muette :

On Saturday September 20, the Saint-Germain-en-Laye Tourist Office will be organizing two sessions of theatrical tours, led by actors, at 2pm and 4pm (duration 40 minutes, open to all). These tours are free of charge, but registration is required from mid-August onwards, via the following address: vieculturelle@saintgermainenlaye.fr

On Sunday September 21, the Pavillon royal de La Muette will be offering classic tours. Registration for these tours will be available on our website from September. Please note that access to the tours is subject to prior registration. Tours will take place from 10am to 6pm.

Come and relive the elegance of a bygone era!