The Premonstratensian Abtei Sayn has guarded the entrance to the Brexbach Valley for more than 800 years. The abbey was established in 1202 by the Sayn Earls. The north wall is adorned with blind arcades and colourful exterior paintings from the 13th century. Magnificent highpoints of the church are the Stumm organ from 1778 and the valuable Simon Shrine with the arm relic of the Holy Apostle Simon (around 1215). Particularly worth seeing at the Roman Cloister with the Well House from the 13th century with unique painting and the noteworthy tombs from various eras.