The Mar Petion Church is named after a martyr of the same name who was educated by his cousin in a monastery and died in 446. It is the first Chaldean Catholic church in Mosul, after the union of the Church of the East with Rome in the 16th century. It dates back prior to the 10th century and lies 3m below street level. This church suffered destruction and it has been reconstructed many times. A hall has been built on one of its three parts in 1942. As a result, most of its artistic features have been lost. Near Bash Tapia is the Ancient Tahira Church (The Immaculate) which is considered one of the most ancient churches in Mosul. No evidence helps to determine its exact location. It could be either the remnants of the church of the Upper Monastery or the ruined Mar Zena Church. Al-Tahira Church dates back to the 7th century, and it lies 3m below street level. A last reconstruction took place in 1743. Mar Ahudeni Church was named after Mar Ahudemmeh (Hudeni) Maphrian of Tikrit who martyred in 575. Mar Hudeni is an old church of the Tikritans in Mosul, dating back to the 10th century. It lies 7 m below street level. First reconstructed in 1970, people can now get mineral water from the well in its yard. The chain, fixed in the wall, is thought to cure epileptics. Located in the north of Mosul, St. George's Monastery (Mar Gurguis) was named after St. George. Most probably it was built late in the 17th century. Pilgrims from different parts of the north visit it annually in spring, when many people travel to its surrounding areas on holiday. It is about 6 m below street level. When a modern church was built over the old one in 1931, much of its archeological significance was lost. The only monuments left are a marble door-frame decorated with a carved Estrangelo (Syriac) inscription and two niches which date back to the 13th or 14th century. The church was completely destroyed on 2014 by ISIS militants. Mar Matti Monastery is a famous monastery situated about 20 km east of Mosul on the top of Mount Alfaf (Mount Maqloub). It was built by Mar Matte, a monk who fled with several other monks in 362 from the Monastery of Zuknin near the city of Amid (Diyar Bakir) in the southern part of Asia Minor (present-day Turkey) and the north of Iraq during the reign of Emperor Julian the Apostate (361-363).