The Monastery of Saint Thaddeus (Armenian: Սուրբ Թադէոսի վանք, Surb Tadeosi vank; Persian: کلیسای تادئوس مقدس, Kelisā-ye Tādeus moghadas) The "Holy Tadeosi Cathedral" is an ancient Armenian monastery in a mountainous area of West Azerbaijan province, Iran.

Also known as Kare Kilisa (the "Stone made Church")[1] (Kare in Armenian translates to "stone," and Kelisa is the Persian word for "church"), this historic site is located approximately 20 kilometers from the town of Chaldiran in Iran, in the region historically referred to as Ancient Armenia in the East.

[4] The Monastery is site of the Pilgrimage of St. Thaddeus which in 2020 was added by UNESCO to its list of Intangible Cultural Heritage.

Simeon, Father Superior of the monastery, added a large narthex-like real Armenian architecture, west extension to the church.

[10] According to Armenian Church tradition, the Apostles Thaddeus and Bartholomew traveled through Armenia in AD 45 to preach the word of God, where many people were converted and numerous secret Christian communities were established.

The ancient Christian historian Moses of Khorene told the following story, considered a legend by most modern historiographers.