Pantheon - one of the most remarkable buildings in Rome - can be visited free of charge.
Piazza S.Pietro in Vincoli 4/a.
The son of the architect, Caravaggio (1573-1610) is considered a true innovator, especially in the use of the strong contrast between kight and dark. His early works attracted the attention of the influential Cardinal Francesco Maria del Monte, who became his first patron in Rome. Many of his Caravaggio's religious works were criticized for their stark realism. As models for his paintings he used peasants and street urchins and prostitutes, even for religous themes.
Gian Lorenzo Bernini (1598-1680) was primarly a sculptor and architect, but also a painter and dramatist. Born in Naples, as a child Bernini family moved in Rome and here you can find most of his works. He is buried in the Basilica of S.Maria Maggiore.
You can find in Rome several walking tours guided by professional guides and free of charge, although tips are welcome if you enjoyed your time. No reservation needed, every day, any weather. Choose one that suites best your time and interests or combine several tours together.
Part of the global initiative started in London - Open House Roma has become a tradition in Italy - one weekend per week (in May, check program www.openhouseroma.org) more than 170 private palaces, mansions, homes, libraries and other buildings open their doors to public. This is a rare opportunity to see places otherwise closed for public admission, especially for art and architecture lovers. All buildings offer free admission, although some of them request prior registration.
Military band concert is performed every first Sunday of a month in front of Italian Parliament on Piazza Montecitorio. The concert starts at 11:00 and lasts about an hour
This 17th century palace is the seat of the Chamber of Deputies since 1871 (Piazza di Montecitorio). Every first Sunday of the month from 10:00 to 17:30 it is open to public.