Journées de l'Architecture 2025: an investigation to be solved at the Maison de Fer de Poissy (78)

Located in Poissy, this strange house with its metal architecture is sure to have already caught your eye. The Maison de Fer is an architectural curiosity in the Yvelines region, often visited during the Journées du Patrimoine (Heritage Days) or the Nuit des Musées (Museum Night). If you'd like to know all the secrets of this exceptional building, don't miss the events scheduled during the Journées nationales de l'Architecture.

This cultural event is the perfect opportunity to find out more about this unique house, which has only 10 equivalents in the whole of France. Its special architecture and history will be revealed at the Journées de l'Architecture on October 18, 2025.

The Journées de l'Architecture are held every autumn. Dozens of venues in Paris and the Île-de-France region take part in this event, offering the chance to (re)discover architectural curiosities and masterpieces, as well as to learn more about the various professions involved in this field, which combines engineering, art, history and heritage.

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Without further ado, here's what's in store at the Maison de Fer this October weekend.

On the program for the Journées de l'Architecture at the Maison de Fer de Poissy:

• Le Mystère de Poissy - Saturday, October 18, 2025 from 2 to 6 p.m.

A crime has just been committed in one of Poissy's monuments. Come and unmask the culprit! Unleash your detective skills and solve the case just like in the famous detective game. An original way to (re)discover the finest treasures of Poissy's heritage and the historical figures associated with the town!

An original program for the curious and the passionate!