San Lorenzo in Piscibus

It is located near Saint Peter's Square and Vatican City, but its façade is not visible from the main street, Via della Conciliazione.

[3] In the 13th and 14th centuries it fell under the care of the Lateran Basilica, as reported in an inventory put together by Nicola Frangipani during the reign of Pope Boniface VIII (1294-1303).

[3] In the Middle Ages the governance of the church was transferred to the canons of the Vatican Basilica, as attested in bulls of Innocent III (October 15, 1205) and Pope Gregory IX (June 22, 1228).

[6] It was during this period that the church's structure, whose facade lay at the south side of Piazza Rusticucci after its confluence with the Borgo Vecchio road, (both have been destroyed in 1936–37 during the destruction of the spina dei Borghi), was incorporated into the nearby palazzi of noble families and more or less became a private chapel of the Cesi family, which owned the nearby palazzo.

[6] During the course of construction, which spanned about a decade from 1936 to 1950,[2] the church's façade was entirely removed and the building hidden inside the yard of the left propylea which delimits Piazza Pio XII.

[2][6] Pope John Paul II saw the old church—by then more or less forgotten, being hidden by the modern propylea around Piazza Pio XII—as a potential site for a youth ministry center at the Vatican.

He reconsecrated it with a special youth Mass in March 1983, expressing the desire that the church become "a hothouse of faith-filled evangelization.

[6] Above the high altar, there used to be a painting depicting the Marriage of the Virgin by Niccolò Bertoni, a student of Carlo Maratta.

View of the campanile
The spolia columns and exposed brick of the Romanesque interior