In the city of the dead underneath the Vatican

On Wednesday morning, Mark and me took off once more to visit the Vatican... but this time we intended to go to a place most tourists don't even know of: the 1st century necropolis underneath StPeter's Basilica. According to the Bible and the old stories and legends, or whatever you want to call them, Peter died crucified up-side-down (he didn't consider himself worthy to be crusified in the same way as Christ) in the circus of Nero (just outside of todays Vatican), and then buried on the slope of a hill next to the circus, the Vaticanum hill. This hill was, until the late 3rd century, a pagan necropolis. Imagine a street going up the hill, and on both sides small houses, mausoleums, for each family, and inside these the sarcophages or urnes of the dead members. Only the most important members of the families had their own sarcophage, most of the other were buried in the the ground of the house. Even the ashes of the slaves were kept close-by. So, when Peter died, he was buried on this hill, but in a very simple way,sinces this was just the beginning for Christianism and the persecutions very high. There were two supportive walls in the ground between which his body was burried, erected by his followers in secret to mark the spot where he rested.
A few centures later, in 313 the Emperor Constantine declared Christianism to be the official state religion. In honor of StPeter, he decided to build a basilica on the hill where he was burried, and the altar should be placed exactly above his tomb. There was already a small mausoleum with two columns (again by the later followers of Peter) which was kept, and well integrated in the altar. The construction works were huge and difficult, as out of a hill they had to make a vast ground to hold the basilica. They "cut off" the top of the hill, and filled the old necropolis with earth, built fortifying foundations and made the basilica on top. Good 12 centuries later this wooden basilica was already too old, fragile, and even dangerous, so, in the early 16th century (1506 - also the foundation of the Swiss Guard;)), a new basilica (the actual one) was built on the exact same spot. Again, a new altar was built right above the old one, using it as a foundation, a glorious bronze canopy, made by Bernini, which, even today, is only used by the Pope.
When we visited all this, we were taken two levels underneath the basilica, and walked on the street which once used to be the main street of the necropolis, with the old houses of the dead on both sides, all with very nice frescoes and mosaics. We could also see the ancient foundations built to support the first basilica. And we made our way up, following the path uphill. We saw what is supposedly the tomb of StPeter, and above it the different layers of altars, as well as his bones (where exactly they are and how they got there is another long story). Finally we emerged one level underneath the basilica, in the Grotto where the Popes (who are not saints yet) have their tombs. The one drawing most attention to it now is of course the tomb of late John Paul II.
Sorry if I got any of the dates wrong, didnt cross check but you can find info on the net if you're interested.