Abbaye Saint-Thierry du mont d'Hor, Medieval abbey in Saint-Thierry, France.

Abbaye Saint-Thierry du Mont d'Hor is a monastery perched on a hill near Reims with preserved medieval structures, including a 12th-century chapter house and manicured gardens. The buildings show how the complex evolved over time, with the original layout still visible throughout the compound.

The monastery was founded around 500 under Theodor of Mont d'Hor and was originally dedicated to Saint Bartholomew. In 974 it was reformed under Benedictine practices and continued this tradition through modern times.

The community here is a Benedictine nunnery, re-established in 1968 by nuns of the Vanves congregation after two centuries without monastic life on the hill. The nuns follow a routine of prayer, hospitality and work, and visitors can join the communal prayer times. The monastery belongs to the Archdiocese of Reims.

The site sits on a hillside and is reached by rural paths that vary in condition depending on season and weather. Sturdy footwear is recommended, and visitors should check ahead to learn when prayer services occur so they can experience monastic life properly.

The 12th-century chapter house is the only structure to survive the 1777 demolition ordered after the community was expelled. Bernard de Montfaucon catalogued the abbey's books in 1739; nearly 150 manuscripts are now mostly held at the Municipal Library of Reims, with a few in the Vatican Library and the Bibliothèque nationale de France.