GS1, on 29 September 2012 - 09:51 PM, said:
Fine , whatever. Why is there a hexagram and a pentagram out front of St Peter's Basilica? Did Jesus like those figures?
Well there aren't really (as others have said) but you can make them fit in if you want to

The pentagram was actually used by Pythagoras and his followers to recognize each other - they thought it was a mathematical perfection and it symbolized health. During the early days of Christianity many Christians wrote the letters S-A-L-U-S (safety or health in latin) in the five points and carried it as an amulet or they would write the letters I-E-S-U-S in it - so there is a connection between Christianity and pentagrams
On another note have you ever been to the Piazza? People have always loved optical illusions and Bernini included some at the piazza - if you stand at a small disk (on the map it's on the teal line between the fountain and the obelisk) and look at the colonnade you'll only see one instead of three rows, this is the exact centre of the colonnade and the other columns are in the shadow of the front row. This I believe explains the teal lines on the map
Someone said that the obelisks were just decoration? They actually do have a function.
The first person to really import obelisks from Egypt were Augustus - he placed a sun on top of it them to show that it was dedicated to the sun.
Later after the knowledge of hieroglyphs had been lost, they became more of a decorative item and the popes placed them in certain places with a cross added to the top.
When pilgrimages were more popular many people travelled to Rome and when you entered the city from the northern gates you would walk right into Piazza Del Popolo - on the Piazza is an obelisk as well as a church. (Many of Rome's streets are very straight and you can see quite far.) From there you could look down the street and see another obelisk marking another church for you to visit on your pilgrimage and from that one another etc.
You can still pretty much follow the obelisks around to some of the most important churches in Rome.