The Vatican

Vatican City is the world's smallest independent state. The Vatican is home to the Pope, the head of the world's Catholics.  Inside the Vatican are St. Peter's Basilica, the Sistine Chapel, and the Vatican Museums. These places have some of the world's most famous paintings and sculptures.

the world's largest church

the dome of St. Peter's 

Michaelangelo's Pieta

A Swiss guard

paintings on the ceiling of St. Peter's. The most impressive are in the Sistine Chapel, this website has a virtual tour of the chapel, http://www.vatican.va/various/cappelle/sistina_vr/index.html