NEW YORK - Pope Francis has officially begun his highly anticipated journey to the Americas.

The pope arrived in Cuba Saturday to share his message of hope and peace. The historic trip is seen as a celebration of a new era of diplomacy between the U.S. and Cuba, and the role that the pope played in thawing the formerly frosty relationship.

Thousands are expected to turn out for an open-air Mass Sunday in Havana's Plaza de la Revolucion. Raul Castro, president of the island nation, is expected to attend in another another sign of change after the Cuban regime had all but banned religion for more than three decades.

After wrapping his Cuba visit, the pope will head to Washington D.C. next week, where he will meet President Barack Obama before traveling to New York on Thursday. While in the city, Pope Francis will lead Mass at St. Patrick's Cathedral, stop by Central Park, address the United Nations, and lead a service at Madison Square Garden.

After his New York City trip, the pontiff will visit Philadelphia before returning to Rome.