HAVANA – President Barack Obama has signed many guest books during his time in office, but the message he left behind for Cubans is one for the history books.

"It is a great honor to pay tribute to Jose Marti, who gave his life for independence of his homeland. His passion for liberty, freedom, and self-determination lives on in the Cuban people today," Obama wrote in dark ink in the book after he laid a wreath and toured a memorial dedicated to the memory of Jose Marti.

Marti was an influential poet and journalist who became a symbol for Cuba's bid for independence against Spain in the 19th century.

Hundreds of Cubans took in the street nearby, waving and taking photos.

Standing next to the president inside the memorial was museum director Aide Diaz Ortega, 96, who told Obama that he was "very kind" for coming to visit the memorial.

Standing in a lineup of Cuba and U.S. officials, the president listened as a military band played both the Cuban and American national anthem. He held his hand on his heart for the "Star Spangled Banner" and watched as three Cuba soldiers carried a massive wreath of red and white roses to the base of the Marti memorial. Obama made no remarks.

The scene was heavy with reminders of Cuba's history.

Behind Obama were striking steel sculptures of two Cuban Revolution figures: Ernesto "Che" Guevara and Camilo Cienfuegos.

In a long-anticipated moment, Obama and Cuban President Raul Castro shook hands warmly and smiled for the cameras as they greeted each other at the Revolutionary Palace.

It was the leaders' first meeting since Obama arrived in Cuba on Sunday and a milestone in the new era of closer relations between the two countries.

Obama and Castro exchanged words briefly, and Obama told Castro about his visit so far through an interpreter saying, "We had a great tour yesterday. Enjoyed it." and "We had a great dinner."

The men then watched a display of Cuban troops. Secretary of State John Kerry, National Security Advisor Susan Rice and several other U.S. officials looked on.

Obama and Castro have met before. They first shook hands in 2013 in South Africa at the Nelson Mandela's funeral.

Havana residents said they hope Obama's meeting with Castro Monday will bring change that betters their lives in concrete ways.

Just before the encounter was set to take place, Marta Rodriguez was waiting for a bus to go to work. She said, "What I hope for is an agreement, an improvement for us."

Roberto Hernandez is a 52-year-old construction worker. He said some things have changed as longtime Cold War foes Havana and Washington repair relations, but added: "I don't see a complete change as the people had expected."

Hernandez said he'd like to see changes that include ending the U.S. embargo, which is also a chief demand of the Cuban government.

Obama has implemented a number of measures poking holes in the embargo, but the power to lift it outright lies with the U.S. Congress.

The leaders held a news conference Monday afternoon, resulted in an extraordinary interchange between CNN reporter Jim Acosta, a second-generation Cuban-American, and Castro, a figure of absolute authority in Cuba who is never subjected to aggressive questioning by the state-controlled press or exposed to questions from independent foreign reporters.

When asked why Cuba has political prisoners, Castro testily addressed Acosta directly, saying "What political prisoners? Give me a name, or names, or after this meeting is over you can give me a list of political prisoners and if we have those political prisoners they will be released before tonight ends."

Cuba is criticized for briefly detaining demonstrators thousands of times a year, but has drastically reduced its practice of handing down long prison sentences for crimes human rights groups consider to be political.

Cuba released dozens of political prisoners as part of its deal to normalize relations with the U.S. and Amnesty International said in its 2015/2016 report that it knew of no prisoners of conscience in Cuba.

Obama also spoke at the news conference, calling it a "new day" in U.S.-Cuba relations.

"For more than half a century, the sight of a U.S. president here in Havana would have been unimaginable. But this is a new day. Es una nueva dia," Obama said.