Patriarchal Monastery of the Holy Trinity (Sveta Troitsa) is located on the right bank of the Yantra River, within its Dervent Gorge, just below the cliffs of Arbanasi Plateau. It is just outside Veliko Tarnovo on the way to the village of Arbanasi and the town of Gorna Oryahovitsa.
According to an inscription discovered during the construction of the present monastery church, Sveta Troitsa was established in 27 January 1070. Another theory states that the monastery was founded later in the mid 14th century, under the rule of Tsar Ivan Alexander, Theodosius Tarnovski and Patriarch Evtimiy of Tarnovo.
When Tarnovo fell under the Ottoman rule in 1393, the monastery was plundered and burned down, but continued to exist, supported by donations from Wallachian and Moldovian rulers. Several of these donation charters have been preserved and could be seen on the site.
The monastery was plundered once more during the Kardzhali (Turkish brigands) raids at the end of the 18th century and was gradually abandoned.
The Patriarch Monastery was re-established in1847 with donations from the local population and located 1km from the original monastery. The monastery church was built by the famous Bulgarian architect Kolyo Ficheto and hand-painted by the famous painter, Zahari Zograf.
The church, along with the entire monastery, suffered extensive damage during and earthquake in 1913. The monastery and the church were reconstructed in 1927. The altar of the current church was brought from the ancient Roman town of Nicopolis ad Istrum.
In 1948 the monastery was converted into a female convent.