
St. Thaddeus monastery or Tatavus church, which is known as the first church in the Christian world, is one of the religious attractions and places of interest in West Azerbaijan province, which is located 20 km from Chaldoran, along with the two churches "Zor Zor" and "St. Stepanos." They are considered one of UNESCO’s World Heritage Sites of Iran.
Those are located in the heart of Turkish and Muslim cities and villages, and the annual gathering of Christians to hold religious ceremonies is accompanied by a significant reception by the Shiites of the region. Some people of the region also host travelers of this Christian religion. Due to their unique architecture, these historical and religious buildings were registered on the World Heritage List in July 2007 at the 32nd UNESCO World Heritage Meeting in Quebec, Canada.