The historic monastery of Dadia was built in the 19th century and renovated in 1912. It is southwest of Soufli, at the edge of the Dadia Forest.
The monastery is built in a Pi-shape (Π) with two parts, which were built between 1834 and 1851. Its church, dedicated to the birthday of Mary, was destroyed by explosion in 1912. Some of the icons are still preserved. A marble plate, on which the Thracian Horseman is represented, was found in the monastery of Dadia and is now exhibited in the Archaeological Museum of Sofia, Bulgaria.
On the path that leads to the monastery, there is a fountain built in 1727, made with a donation by the guild of farmers. Dadia monastery celebrates on 8 September.