Italy
I recommend this area because it is full of things to see and to experience too.
Let's start from the Basilica of Saint John in Lateran, the cathedral of the Pope, the main Basilica in the world for Catholics.
This is unique because there are different styles and the result is perfect. In case you want to know more about the complex, you can get an audio guide at the information point which is beside the statue of Constantine in the main porch.
Other interesting sights include; the 12th century cloister; the Baptistery (the Basilica and the Baptistery were the very first Christian sites in Rome); the Scala Santa that was walked on by Jesus on his way to trial by Pontius Pilate and brought from Jerusalem in the 4th century by Emperor Constantine’s mother, St. Helena; the Sancta Sanctorum, the private chapel of the Popes and the Triclinium where you can see the very first flag of the Vatican State.
You need to spend at least 2 days within this area because nearby you can visit the Basilica of the Holy Cross of Jerusalem, the small and cosy church of the SS 4 Coronati and its cloister, visit the Villa Celimontana Park, the church of SS Giovanni e Paolo, the very well preserved Roman houses of the Celio, they are located just beside the church.
Remember, just in front of the Basilica of Saint John in Lateran you can get the bus 218 (blue one) that will take you directly to the Catacombs.
Metro Linea A-B and Bus N. 16-81-85-87-117-186-218-650-714-850.
Iam Italian, I read 6 pages of tips and, regarding Rome, I was surprised that nobody seems to have visited San Pietro in Vincoli, an otherwise unimportant church but one that contains the statue of Moses by Michelangelo. The first time I saw it I felt like I was in the presence of God and I am not a believer.
It is in Via Cavour, you can walk there from the Stazione Termini in 15 or 20 minutes, then on your left there are stairs leading to the church. I am sorry I cannot give better directions, maybe there are signs - anyway you can ask the tourist bureau.
The labyrinthine, subterranean graveyards of the city's early Christians will remain the most memorable experience of a trip here. No grand views, no Roman poseurs to ogle, just an immersion (literally) in the rituals of early first millenia Italians.
The catacombs are at various locations around the city
You always have to queue so get there one hour early and walk through all the rooms directly to the Sistine Chapel, ignore the rest or do another time; then you arrive ahead of the crowds able to glory in it without the noise and hub-bub. Many people take mirrors to look down into to save their necks.
mv.vatican.va/3_EN/pages/MV_Home.html
Virtual Tour
mv.vatican.va/3_EN/pages/CSN/CSN_Main.html
Transport
mv.vatican.va/3_EN/pages/z-Info/MV_Info_Trasporti_02.html
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