These are the top historical and religious sites to visit as King Charles and Queen Camilla prepare their own April tour.

St. Peter's Basilica is one of the most revered - and visited - religious sites in the world. Do you need any tickets to see its legendary architecture and art?

The Conversation U.S. asked Daniel Speed Thompson, a theologian at the University of Dayton, for some insight into Vatican City. The Vatican houses the central government of the Catholic Church ...