The Tvrdoš Monastery is located on the right bank of the Trebišnjica River, 5 km west of Trebinje. It was built on the foundations of a church from the 4th century and is one of the oldest cultural and historical monuments in the Republic of Srpska. In the 16th and 17th centuries, Tvrdoš was the seat of the Humsko-Herzegovina, that is, Trebinje Metropolitanate. During the Turkish-Venetian war, the monastery was destroyed, and part of the relics were transferred to the Savina monastery (Herceg Novi) and the Duži monastery , from where the hand of Saint Queen Jelena of Anjou , mother of kings Milutin and Dragutin, was transferred to Tvrdoš in 1992. The monastery is also known for the fact that Saint Vasilije Ostroški received monastic tonsure and priestly rank in it, after which he served for a certain period as parish priest of Popovopolje. This is the reason why Saint Vasilije is also called “Ostroški and Tvrdoški”. The revival of the monastery began in 1955, when the entire monastery complex was renovated. The special feature of the interior of today’s church is the glass floor, which represents a kind of “window into the past” through which the foundations of the church from the 4th century can be seen. The long tradition of wine production, whose beginnings date back to the 15th century, is successfully maintained by the monastery even today thanks to restored vineyards, a wine cellar and a modern winery.