While legend has it that a church founded by Charlemagne once stood on this site, the current Peterskirche, built in the early 18th century, now stands on the site of an ancient 12th-century temple. The church owes its lines to St. Peter's Basilica in the Vatican City, the temple on which the design for this church is inspired, though its dimensions are, of course, much smaller because of the limits imposed by the location. 

Indeed the fact that Petersplatz, the square behind the Graben where the Peterskirche is located, is so narrow is precisely what lends the church its particular character, in which the vertical dimension of the building is more prominent. Other solutions, such as the oval dome, are other clever means of dealing with the reduced space available.

Thanks to the joint efforts of the architects, among which Gabriele Montani played a particularly important role, and the artists who worked on the elaborate decoration, Peterskirche is the most beautiful and spectacular Baroque church in the city. The building, completed by Hildebrandt, welcomes the visitor through a splendid portico by Andreas Altomonte.

The building is crowned by representations of the three theological virtues, faith, hope and love, in lead work by Franz Kohl.

Highlights of the lush interior, which is flooded with natural light provided by eight large windows, include, above all, the ornate gold pulpit created in 1716 by the sculptor Matthias Steinl, and representing the Holy Trinity, and a twelve-year-old Jesus teaching in the temple.

Also notable is the representation dedicated to the martyr Saint John of Nepomuk, created by Lorenzo Mattielli in 1729. The priest, confessor to the Queen of Bohemia, was thrown into the Vltava river in 1393 for refusing to reveal certain secrets of the confessional to King Wenceslas IV. The five stars in the water are the symbol of the Latin word "tacui"s (I remain silent).

Also impressive are the frescoes by Johann Michael Rottmayr that decorate the huge dome, depicting the Assumption of the Virgin, which were painted almost single-handedly over a period of about two years from 1713 to 1714.

Undoubtedly the most striking feature on entering the church is the high altar, designed by Galli Bibiena, which features a large altarpiece by Martino Altomonte depicting the healing of a lame man by the apostles St. Peter and St. John at the gates of the Temple of Jerusalem and, beneath this, a beautiful image of the Immaculate Conception by Leopold Kupelwieser.

The church houses chapels dedicated to, among others, Saint Barbara, Saint Sebastian and the Holy Family. Below the altarpiece dedicated to the last of these is a portrait of Josemaria Escrivá de Balaguer, the founder of Opus Dei, which stands above the glass coffin of San Donatus, one of the martyrs buried here. There is also a beautiful chapel dedicated to St. Francis de Sales, where visitors can contemplate an impressive altarpiece depicting a dead child being brought back to life by the saint, also designed by Rottmayr.

Music is also a very important element in this church, a fact that is reflected in the magnificent 2200-pipe organ, richly decorated in rococo style by Matthias Steinlen.

This church is also known for housing the relics of some of the early Christian martyrs, including Saint Benedict. 

As a curiosity, rumour has it that Empress Sisi used to come here incognito to pray late at night. 

Without a doubt, this is a place of rare beauty. In addition, visits can be made even more enjoyable if they are accompanied by music, and daily concerts are held, if the times have not changed, from Monday to Friday at 3 pm and on weekends at 8 pm. By the way, these concerts are free.