St. John, also called Surb Hovanes, is a 5th-century church in Mastara village whose layout became distinctive enough that later churches built along the same lines are classified as "Mastara-type."
The building follows a variation of the cruciform (cross-shaped) plan, topped by a central dome — a pairing that gives the type its name rather than any single decorative feature.
The church stands in Mastara village, Aragatsotn region, roughly 61 km west-northwest of Yerevan as the crow flies.
