Concathedral

A co-cathedral is a cathedral church which shares the function of being a bishop's seat, or cathedra, with another cathedral, often in another city (usually a former see and/or the civil capital). Instances of this occurred in England before the Protestant Reformation in the dioceses of 'Bath and Wells,' and of 'Coventry and Lichfield.' These two dioceses were each named for both cities that served as bishop's seats.

In Albania, the Roman Catholic Archdiocese of Tirana-Durrës has a co-cathedral in Durrës, Saint Lucia co-cathedral.

In Belgium, the cathedral of the primatial Roman Catholic Archdiocese of Mechelen-Brussels is the metropolitan St. Rumbold's Cathedral in Mechelen, the archiepiscopal seat. Its co-cathedral is the Cathedral of St. Michael and St. Gudula in Brussels, the state capital. A third, larger church in Koekelberg (also in Brussels) has the status of basilica, not cathedral rank, yet it has received papal visits including a papal beatification.

The Roman Catholic Diocese of Sofia and Plovdiv has, besides the Cathedral of St Louis in Plovdiv, a new co-cathedral in Sofia, the Cathedral of St. Joseph

The Metropolitan archbishop of Split-Makarska has, in Split (Dalmatia), the co-cathedral of Saint Peter the Apostle Konkatedrala sv. Petar Apostola, besides his episcopal see, Katedrala Sv. Dujma.

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