The Ustrem monastery “Holy Trinity”, known also as the Vakuf monastery or the Haydоuk monastery, is situated in the Sakar mountain, some 3km away from the village of Ustrem (known as Vakuf until 1934).
Traditionally, the origin of Bulgaria’s cult centres can be traced back to pagan sanctuaries of Thracian and Slavonic tribes. The Ustrem monastery does not represent an exception. The presence of Thracian people in these lands is inferred from the excavation of a large Thracian earthen jar and remains of walls on the other bank of the small Monastery River, where the monastery vineyard was once to be found. It is believed that the Orthodox monastery was established during the Second Bulgarian State, while its name is mentioned in early 15th-century documents of the Ottoman Empire. A 5m deep and 4m high and wide cave that hosted the first Christian church of the monastery lies close to the present-day cloister. According to a legend, a man named Peter arrived at the cave (later named as “The Old Church” and “the Cave of Kara Kolyo”), carrying with him two icons – of the Holy Trinity and of St. Apostles Peter and Pavel. The man left the two icons inside the cave and settled with his flock of sheep close to the monastery. In 1725, after a dream he had, the man sold the flock and with the help of people from near-by villages, built the St. Apostles Peter and Pavel chapel, over which the present-day church was erected. It was most likely upon the emergence of so-called Kurdzhalii bands that plundered and harassed villages in the area, when the monastery and the church were damaged seriously. In late 18th century – early 19th century, the area fell under the protection of Indzhe voivode, who took care of the Vakuf monastery. It is quite probable that Indzhe himself sent the famous haidouk Hristo, who was already of old age and wished to abandon the secular way of life, to restore the monastery. According to some historical data, Hristo voivode became a monk with the name of Hrisant and initially lived in the above-mentioned cave. From here, he invited the nearby villages of Vakuf (Ustrem), Novo Selo (Mramor), Srem and others to start reconstruction of the cloister. This is wherefrom one of the popular names of the monastery – the Haidouk monastery - came. The first church, the so-called Peter’s temple, was ruined down, and a new church dedicated to St. Apostles Peter and Pavel was built in its place. Two fountains were constructed, too, with one of these having a stone plate with the images of St. Apostles Peter and Pavel. This plate is currently kept at the National Museum of History in Sofia. The monastery was named after the nearby village of Vakuf, while Hrisant became its father superior. Gradually, the Vakuf monastery became the biggest spiritual centre of the area. In 1918, due to a raging plague, many a man sheltered at the monastery, donating their riches to the monkhood. Granaries, a kitchen and the eastern and northern wings were built precisely with the help of those donations. Unfortunately, all these buildings caught fire in 1951 and were destroyed. In 1836, the monks of the enriched monastery decided to build a bigger church. Skilled masters managed to integrate the St. Apostles Peter and Pavel chapel into the new church. The new iconostasis of the church was made after the pattern of the old one. The icons were painted by unknown masters in the first half of last century. Until 1909, the monastery represented a monkhood. In the middle of August, 1909, about 50 nuns from the villages of Studena (Elhovo region) settled into it. The mother superior, Evpraksia, traveled throughout most of Bulgaria and Russia, bringing back plenty of money donations that helped pay back the monastery’s huge debts. The Vakuf monastery, together with the Cave of Kara Kolyo have been declared monuments of culture.
The monastery receives guests from all over the country throughout the year. Its capacity is 40 beds. In the month of June each year (on June 16), people from nearby and distant towns and villages flock to the monastery from its holiday and the accompanying fair. Reconstruction of the eastern wing of the monastery that was destroyed by fire in 1851 is still pending. The engineering project for reconstruction of the building is already finished, but the monastery continues to raise the needed funds.
If one comes from Topolovgrad, there is an off-road to the monastery that starts right after one passes through the village of Mramor and before one reaches the village of Ustrem. The road from Yambol, in turn, goes by the village of Srem that perches on the left bank of the river of Tundzha. To the right, one can see the first hills of the Sakar mountain. The off-road to the monastery is to the left from the main road that runs from the village of Ustrem to the town of Topolovgrad. Both roads to the monastery are asphalt-covered, but the first option (from Topolovgrad) is recommended as the road has been repaired only recently.