The Boniface Chapel on Hülfensberg is an important religious building in the Eichsfeld region of Thuringia, near Geismar. It was built in 1903 and stands on the foundations of an earlier princely chapel, donated in 1716 by Landgrave Christian of Hesse-Wanfried. The chapel belongs to the Franciscan monastery of Hülfensberg and is part of the parish of St. Ursula Geismar in the Diocese of Erfurt.
Hülfensberg itself was already a place of worship in pre-Christian times. Popular belief connects it with the legendary felling of the Danube Oak by Saint Boniface – although historically, Geismar near Fritzlar in Hesse is more likely to be the location. The chapel bears the patronage of Saint Boniface, who is venerated as the "Apostle of the Germans."
Architecturally, it is a rectangular building with a three-sided chancel in the Romanesque style. Particularly impressive is the high altar, which depicts the felling of the Danube Oak – a work by the artist Franz Albermann. The chapel is attached to the larger pilgrimage church, which is in the early Gothic style. This church measures 22.24 meters in length and 17.12 meters in width. A special feature is the slope of the interior floor: from the main portal to the communion rail, the floor drops by a full 64 centimeters.
Hülfensberg is one of the oldest and most important pilgrimage sites in the Eichsfeld region. The pilgrimage tradition dates back to the Middle Ages, with the first documented mention in 1351. A special destination for pilgrims is the famous Romanesque cross from the 11th century, depicting Christ as a victorious king. According to legend, it was brought by a crusader from the Holy Land.