Conventual church in the context of "Santa Croce in Gerusalemme"

A katholikon or catholicon (Greek: καθολικόν) or sobor (Church Slavonic: съборъ) refers to one of three things in the Eastern Orthodox Church:

• The cathedral of a diocese.
• The major church building (temple) of a monastery corresponding to a conventual church in Western Christianity.
• A large church in a city at which all the faithful of the city gather to celebrate certain important feasts rather than go to their local parish church.

The name derives from the fact that it is typically the largest church where all gather together to celebrate the major feast days of the liturgical year. In Russia, it is common for a katholikon to have a smaller church in the basement which can be more easily heated in the winter. A katholikon may have special architectural features in it, such as a cathedra (episcopal throne), or both an esonarthex (inner-narthex) and exonarthex (outer narthex), used for special services such as the Paschal vigil or a lity.

The Church of Saint Susanna at the Baths of Diocletian (Italian: Chiesa di Santa Susanna alle Terme di Diocleziano) is a Catholic parish and Cistercian conventual church located on the Quirinal Hill in Rome, Italy. There has been a titular church associated to its site as far back as AD 280. The current church was rebuilt between 1585 and 1603 for a community of Cistercian nuns founded on the site in 1587 and still based there.

The church served as the national parish for residents of Rome from the United States from 1921 to 2017, during which period the pastoral work of the parish was assigned to the Paulist Fathers, a society of priests founded in the United States. The Paulist Fathers' ministry to United States Catholics subsequently moved to San Patrizio (Saint Patrick).

The Basilica dei Santi Giovanni e Paolo, known in Venetian as San Zanipolo, is a Catholic minor basilica and Dominican conventual church in the Castello sestiere of Venice, Italy.

It is one of the largest churches in the city of Venice. After the 15th century the funeral services of all of Venice's doges were held here, and twenty-five doges are buried in the church.