Topic summary
Abbey church

Extracted from the Wikipedia article Church (building).
Cathedral
A church with a cathedral function is not necessarily a large building. It might be as small as Christ Church Cathedral in Oxford, England, Porvoo Cathedral in Porvoo, Finland, Sacred Heart Cathedral in Raleigh, United States, or Chur Cathedral in Switzerland. However, frequently, the cathedral, along with some of the abbey churches, was the largest building in any region.