Surb Astvatsatsin (Holy Mother of God) Church of Arnei was completed in 1321. It is located on the top of a high hill that overlooks Arpa River and the same name village in Vayots Dzor Region.

St. Astvatsatsin Church has a single drum and a conical umbrella type dome belonging to a domed-all type church. The lintel has a bas-relief depicting the Virgin Mary which together with other carvings of the church belong to the works of the legendary Momik Vardapet, who is also considered to be the architect of the church.

The vicinity of the church is rich in tombstones and khachkars. The ruins of a 13th-century royal palace are spread near the church. It was founded by lord Tarsaitch Orbelian who moved from Yegheghis to Areni at that time. Ruins of a 13th-century bridge built by Bishop Sarkis in 1265-1287 are to the northeast one kilometer. At the same location are the remains of an older bridge.