One of the thousands of attendees at Pope Francis's Havana Mass in the Plaza de la Revolución on Sunday, Sept. 20, 2015. (Julie Schwietert/Fox News Latino)
These university students, who are Catholic, attended Pope Francis' Mass at the Plaza de la Revolución and say they hope his words will resonate with all Cubans. (Photo: Julie Schwietert Collazo/Fox News Latino)
A woman leaves a message for Pope Francis at Sacred Heart Church in Havana. The pope made a visit here several hours after his Mass in the Plaza de la Revolución. (Julie Schwietert Collazo/Fox News Latino)
Crowds record for posterity Pope Francis' arrival in Havana's Plaza de la Revolución. (Julie Schwietert Collazo/Fox News Latino)
Parishioners in Havana and the other Cuban cities the pontiff visited have had to endure the strong anti-Catholic measures put in place by Castro in the first few decades of his regime.