Santa Maria del Popolo
The architect or architects of this innovative project remain unknown due to a lack of contemporary sources. Giorgio Vasari in his "Lives" attributed all the important papal projects in Rome during Sixtus IV to a Florentine, Baccio Pontelli including the basilica and monastery of Santa Maria del Popolo. Modern researchers deemed this claim highly dubious and proposed other names among them Andrea Bregno, a Lombard sculptor and architect whose workshop certainly received important commissions in the basilica. The fundamental differences between the façade and the interior suggest that maybe more than one architect was working on the building.
Basilica of Saint Servatius
Between 1866 and 1900 the church underwent major restorations during which some of the damage done earlier in the century was reversed. The restoration was led by famous Dutch architect Pierre Cuypers. In 1955 a fire caused Cuypers' Gothic Revival westwork spire to fall through the roof of the church, which made another thorough restoration necessary (1982–1991). During this latter restoration, Cuypers' colourful interior decoration scheme was largely removed. During this most recent restoration, extensive excavations that were carried out in the church and adjacent buildings, revealed a wealth of information about the history of the church and its predecessors.