The patriarch's monastery "Sveta Troitza" /Holy Trinity/, Veliko Turnovo District, is built under the western slopes of the Arbanassi's Plateau, hugged under the beautiful steep rocks of the eastern slope of the canyon-shaped gorge of the Yantra River. The monastery has existed ever since the period of the Second Bulgarian Kingdom. It has been one of the centres of spiritual life and has been supported by the aristocracy. Here is made the famous writing reform in the ancient Bulgarian writing style which is afterwards distributed all over the Slavic countries. Monk Evtimii, who is chosen for a patriarch in 1371, has been working in this monastery. After the fall of Bulgaria under the Ottoman yoke the monastery is plundered and destroyed.

In 1847 the monastery is renovated but no one can tell whether the renovated complex is at exactly the same place of the old monastery. Some remains of old buildings have been discovered to the north of the present-day monastery in XIX c. Kolyo Ficheto builds a new church which is seriously damaged after the earthquake of 1913. During repair works in 1927 many of the original parts, built by the Revival period master-builder are changed and simplified.

Irrespective of the fact that the historic and artistic values of the monastery "Sveta Troitza" have been plundered, destroyed or scattered, it has preserved some masterpieces till present days such as: the magnificent icon "Archangel Michael" from 1663 and that of the "Holy Trinity" from 1708. The iconostasis of the monastery church has interesting icons of "Saint Atanasii", "Virgin Mary" (1861), "Jesus the Almighty", "The New Testament Trinity", "Joan the Baptist" and beautiful wood-carved royal gates from XIX c.