St. Peter the Apostle's Church is the main church of Fiuggi. The building was built in the seventeenth century, on the site of a temple of small dimensions dedicated to Saint Lucia, and it was consecrated in 1677. Current Collegiate is spread over a Latin cross, with three chapels on the right side dedicated to St. Francis, Our Lady of Mount Carmel and Assumption, and three chapels on the left side dedicated to Our Lady of Purgatory, Ascension and Sacred Heart. It was restored in 1969 and since then is no longer visible the choir in inlaid wood. Beside stands archpriest's house, previously municipal residence, with mullioned windows in the main facade.