<P> The part of the colonnade that is around the ellipse does not entirely encircle it, but reaches out in two arcs, symbolic of the arms of "the Catholic Church reaching out to welcome its communicants". The obelisk and Maderno's fountain mark the widest axis of the ellipse . Bernini balanced the scheme with another fountain in 1675 . The approach to the square used to be through a jumble of old buildings, which added an element of surprise to the vista that opened up upon passing through the colonnade . Nowadays a long wide street, the Via della Conciliazione, built by Mussolini after the conclusion of the Lateran Treaties, leads from the River Tiber to the piazza and gives distant views of St. Peter's as the visitor approaches, with the basilica acting as a terminating vista . </P> <P> Bernini's transformation of the site is entirely Baroque in concept . Where Bramante and Michelangelo conceived a building that stood in "self - sufficient isolation", Bernini made the whole complex "expansively relate to its environment". Banister Fletcher says "No other city has afforded such a wide - swept approach to its cathedral church, no other architect could have conceived a design of greater nobility...(it is) the greatest of all atriums before the greatest of all churches of Christendom ." </P> <P> There are over 100 tombs within St. Peter's Basilica (extant to various extents), many located beneath the Basilica . These include 91 popes, Saint Ignatius of Antioch, Holy Roman Emperor Otto II, and the composer Giovanni Pierluigi da Palestrina . Exiled Catholic British royalty James Francis Edward Stuart and his two sons, Charles Edward Stuart and Henry Benedict Stuart, Cardinal Bishop of Frascati, are buried here, having been granted asylum by Pope Clement XI . Also buried here are Maria Clementina Sobieska, wife of James Francis Edward Stuart, Queen Christina of Sweden, who abdicated her throne in order to convert to Catholicism, and Countess Matilda of Tuscany, supporter of the Papacy during the Investiture Controversy . The most recent interment was Pope John Paul II, on 8 April 2005 . Beneath, near the crypt, is the recently discovered vaulted 4th - century "Tomb of the Julii". (See below for some descriptions of tombs). </P> <Ul> <Li> In the towers to either side of the facade are two clocks . The clock on the left has been operated electrically since 1931 . Its oldest bell dates from 1288 . </Li> <Li> One of the most important treasures of the basilica is a mosaic set above the central external door . Called the "Navicella", it is based on a design by Giotto (early 14th century) and represents a ship symbolizing the Christian Church . The mosaic is mostly a 17th - century copy of Giotto's original . </Li> <Li> At each end of the narthex is an equestrian figure, to the north Constantine the Great by Bernini (1670) and to the south Charlemagne by Cornacchini (18th century). </Li> <Li> Of the five portals from the narthex to the interior, three contain notable doors . The central portal has the Renaissance bronze door by Antonio Averulino (called Filarete) (1455), enlarged to fit the new space . The southern door, the Door of the Dead, was designed by 20th - century sculptor Giacomo Manzù and includes a portrait of Pope John XXIII kneeling before the crucified figure of Saint Peter . </Li> <Li> The northernmost door is the "Holy Door" which, by tradition, is walled - up with bricks, and opened only for holy years such as the Jubilee year by the Pope . The present door is bronze and was designed by Vico Consorti in 1950 and cast in Florence by the Ferdinando Marinelli Artistic Foundry . Above it are inscriptions commemorating the opening of the door: PAVLVS V PONT MAX ANNO XIII and GREGORIVS XIII PONT MAX . </Li> </Ul>

Which of the four plans of st peter's basilica is represented in the image below