History of the Domaine de Bierville, Marc Sangnier’s pacifist château in Essonne, and opening for the 2026 Heritage Open Days
Bierville: the pacifist château of Essonne opens its doors this Sunday
A pacifist stronghold founded by Marc Sangnier in 1921, and host to international peace congresses from 1926 onwards, the Domaine de Bierville in Essonne will exceptionally open its park on Sunday 20 September 2026.
Editorial journal · Carte des Châteaux ·
Closed to the public for the rest of the year, the Domaine de Bierville in Boissy-la-Rivière, Essonne, will exceptionally open its park on Sunday 20 September 2026 as part of the Heritage Open Days. Behind this discreet name lies one of the most significant sites of French pacifism in the interwar period: it was here that Marc Sangnier hosted international peace congresses from as early as 1926, before the estate became a refuge for families fleeing the persecutions of the 1930s.
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