THE VATICAN GROTTOES
Under the floor of St. Peter's Basilica there is a 3 metre high crypt: the interspace between the Constantinian basilica and the floor of the church: these are the Grotte Vaticane, the crypts or caves, under which the Necropolis (1st-4th century AD) with the tomb of St. Peter is located.
Access to the Grottoes from the Basilica is free (leading down from the pier of St. Andrew).
At the end of the 16th century, Clement VIII had a semi-annular corridor added which connected to the Confession and connected to the medieval crypt.
The Confession (traditionally the space above a relic, protected by a gate to insert objects that became "by contact" relics) is under the papal altar and is aligned – with respect to the necropolis below - with the tomb of the Apostle. It cannot be reached from the Grottoes because the arch that frames it is protected by glass: it is adorned with precious materials and a mosaic portraying Christ (9th century).
In the early 1600s, Paul V enlarged the Grottoes having them adorned with frescoes with views of the ancient basilica and by displaying precious remains of the dismantled church (today's Archaeological Rooms).
Urban VIII had four chapels - at the base of the piers - connected to the Basilica by stairs and to the semi-annular corridor by other corridors.
The crypt has the shape of a three-aisled church and is 50 meters long, with modern "national chapels" (20th century) Irish, Polish, Lithuanian, Mexican, of the patron saints of Europe Benedict, Cyril and Methodius, and the oratory with tomb of Pius XII.
Not all of these spaces are open to visitors (they are protected by gates and only partially visible), to enter them you need special permits or have to participate in private celebrations.
In the exit corridor, sections of the masonry and column bases of the ancient basilica can be seen.
In the Grottoes there are tombstones and tombs of 20 popes (not all popes are buried in the Vatican: 148 out of 264).
Illustrious names such as Boniface VIII, who "invented" the Jubilee, Pius VI Braschi, captured by the French and who died prisoner in 1799, Adrian IV († 1159) the only English pope, as well as the popes of modern times, Blessed Pius XII Pacelli († 1958), St. Paul VI († 1978), and John Paul I Luciani († 1978), who reigned only 33 days.
There are also lay-people with important historical prominence: the Stuarts, pretenders to the English throne, in exile in Rome since 1717 and emperor Otto II who died in Rome at the age of 28.
The Czech Cardinal Josef Beran also deserves a mention: he was arrested in Prague during the Nazi occupation and interned in the Dachau concentration camp; in 1946 he became archbishop of Prague but under communism he was imprisoned as an opponent. Released in 1963, in 1965 he became a cardinal.
Curiosity: the buried women and a new and empty tomb
There are also two women: the eccentric Cristina of Sweden (†1689) born Protestant, who abdicated the throne to become Catholic, and Queen Charlotte I of Cyprus, who struggled all her life to assert her dynastic rights, traveling around various courts. Also a guest of Sixtus IV, she is portrayed in the Sistine chapel (Discourse of the mountain, woman with blue dress on her knees).
Since 2016 there is a white sarcophagus without inscriptions, which will house the body of Benedict XVI.