The Chateau-Thierry Bridge Keystone

The Curator’s Collection highlights the recovery and preservation of the Chateau-Thierry bridge keystone, a World War I artifact originally placed as a foundation stone at Pershing Hall in Paris in 1928. Taken from the destroyed bridge across the Marne River at Chateau-Thierry, the stone commemorates where American troops helped stop the German advance on Paris in July 1918.

After Pershing Hall was sold in 2018, ABMC assumed responsibility for its World War I collection. During renovations, the complete keystone was discovered behind a false wall near the entrance and carefully removed by professional conservators in early 2020, revealing a lead box containing historic documents beneath it.

Now stabilized, cleaned, and transferred to the collection’s repository at Chateau-Thierry Monument, the keystone has returned to the community where it first became part of wartime memory. Its recovery reflects ABMC’s ongoing commitment to preserving historic objects for research, interpretation, and public engagement.

This poster recalls the strategic importance of the Chateau-Thierry bridge over the Marne River, where American forces helped stop the German advance toward Paris in 1918. The bridge’s destruction and the later preservation of its keystones, became lasting symbols of American sacrifice, French gratitude, and the shared memory of World War I. 

This image shows the aftermath of the destroyed Chateau-Thierry bridge, a site closely tied to the fighting along the Marne River in 1918. Its ruins marked the place where American troops helped halt the German advance toward Paris, transforming the bridge into a powerful symbol of sacrifice, resilience, and Franco-American cooperation.

In 1938, as Nazi German aggression raised fears of another war, the French government sent a second keystone from the old Chateau-Thierry bridge to the United States as a gesture of friendship and hope for American support. Arriving in Brooklyn, New York, it was installed by the American Legion during a 1940 parade and ceremony on the grounds of the Bronx Supreme Court building, where it remains today.

These photos trace the rediscovery and preservation of the Chateau-Thierry bridge keystone placed in Pershing Hall in 1928. Hidden behind a false wall for nearly a century, the 600-kilogram stone was carefully removed by conservators in 2020 and returned to Chateau-Thierry, where it continues to connect the city’s World War I history with ABMC’s preservation mission.

These photos show the keystone installed in the Chateau-Thierry Monument Visitor Center, near where it first became part of World War I history. Its return helps visitors connect the 1918 fighting along the Marne River with ABMC’s mission to preserve and share these stories.