The Church of Saint John (Surp Hovanes), also known as Mastara Church, in Mastara, Armenia dates from the 5th century. It features a variation of the cruciform plan and central cupola'd church. In accordance with its square plan, the four projecting apses, inward-facing circular and outward facing polygonal, offer the requisite supports to hold up the imposing polygonal cupola. The complex church designs are like those in Avan and St. Hripsime Church, Echmiadzin.

The works of medieval architecture in Mastara include, among others, numerous khachkars.

• 
  View from the northwest
• 
  View from the southeast
• 
  Detail of inscriptions above the western entrance.
• 
  View of an inscription on the western wall.
• 
  Southern window detail
• 
  Interior view of the dome

• Armenian Architectural Studies: Mastara
• Armeniapedia.org: Mastara Church
• Armenica.org: Mastara Church
• Rensselaer Digital Collections: Mastara