ACCRA, Ghana — America's president and Africa's son, Barack Obama dashed with pride onto the continent of his ancestors yesterday, challenging its people to shed corruption and conflict in favor of peace. Campaigning to all of Africa, he said "Yes you can."

"I say this knowing full well the tragic past that has sometimes haunted this part of the world," Obama told a riveted Ghanaian Parliament. "I have the blood of Africa within me."

In the faces of those who lined the streets and in many of Obama's own words, this trip was personal. Beyond his message, the story was his presence — the first black U.S. president coming to poor, proud, predominantly black sub-Saharan Africa for his first time in office.

The emotional touchstone of his visit: a tour of Cape Coast Castle, the cannon-lined fortress where slaves were kept in squalid dungeons, then shipped in chains to America through a "Door of No Return" that opens to the sea.

Obama absorbed the experience with his wife, Michelle, and their girls, Sasha and Malia.

"I'll never forget the image of my two young daughters, the descendants of Africans and African-Americans, walking through those doors of no return but then walking back (through) those doors," he said later at a grand departure ceremony. "It was a remarkable reminder that, while the future is unknowable, the winds always blow in the direction of human progress." Ghanaians lined up on the tarmac lingered for a time even after Air Force One disappeared into the nighttime sky.

The White House said Obama held no big public events in a city frenzied to see him because Obama wanted to put the light on Africa, not himself. But reality proved otherwise.

Obama billboards dotted the roads. Women wore dresses made of cloth bearing his image. Tribal chiefs, lawmakers, church leaders, street vendors — to them, it felt like history.

"All Ghanaians want to see you," lamented Ghana's president, John Atta Mills, before honoring Obama at a breakfast banquet with hundreds of guests at the coastal presidential castle.

To their disappointment, most people did not see him. The lack of open events and the heavy security kept many in this West African nation away from Obama. They watched him on TV.

Overall, there was no dampening the tone of joy.

"It makes us proud of Ghana," said Richard Kwasi-Yeboah, a 49-year-old selling posters of the American president. "We're proud he chose us. It proves that Ghana is really free."

At the heart of Obama's message here: African nations crippled by coups and chaos, like Ghana has been in the past, can reshape themselves into lawful democracies.

The Obamas are back home after their whirlwind tour, arriving at Andrews Air Force Base early this morning, just after midnight.