Pope Benedict XVI will visit a far larger and more diverse diocese when he touches down in Washington this week than the one that Pope John Paul II found during his 1979 visit.

Since the last papal tour, the number of Catholics in the Archdiocese of Washington has leapt 45 percent from 400,000 to more than 580,000 people. Growth in the diocese, which covers D.C. and suburban Maryland, is being driven by immigration. While Masses here were performed in seven languages in 1979, they are now celebrated in more than 20 languages ranging from Spanish to Nigerian Igbo.