Two million pilgrims are expected to join Pope Francis at World Youth Day in Rio de Janeiro, Brazil, next week.
Held every two or three years, the celebration brings Catholics between the ages of 16 and 35 to worship together.
The celebration will last five days, from July 23 to 28, and include various prayer sessions, classes and masses.
The closing mass will be led by Pope Francis, himself a South American. He is from Buenos Aires, Argentina.
The weather is expected to be sunny and 75 degrees Fahrenheit.
World Youth Day was last held in Madrid in 2011.
