Sights to see, Tours to do in Rome depends also on how many days you stay in Rome:

Here only a few  examples through the endless treasures of the Eternal City, some are “musts” when in Rome.

In Rome for 2 days:

• Ancient Rome: Colosseum, Forum Romanum and Palatine Hill
• Baroque Rome: Churches and Squares in the City Centre, searching for Bernini and Borromini
• Vatican Museums, Sistine Chapel  and St.Peter’s Basilica

In Rome for 3-4 days

• Basilica of S.Clemente and its underground levels – a interesting time time machine of 2000 years in one single place
• The 4 Papal Churches (S.Peter, S.Paul, S.Giovanni, S.Maria Maggiore)
• The Roman Ghetto and its Monuments
• Via Appia and its catacombs
• Fiction: Angels and Demons: On the track of Dan Brown

In Rome for 7 days

• Tivoli: Villa d’Este, Villa of Hadrian
• Ancient Harbour of Rome: Ostia Antica
• Caelius Hill: Case Romane
• Roman Acqueducts

… and many more