Barack Obama laid a wreath at a military grave before attending an open-air concert on Sunday in the lead-up to his inauguration as the 44th president of the United States.
Walking side by side, Mr Obama and US Vice-President-elect Joe Biden placed a wreath at Arlington National Cemetery's Tomb of the Unknowns in Washington.
Joined by tens of thousands of Americans, Mr Obama and Mr Biden later braved a cold winter's day to take in a concert on the steps of the Lincoln Memorial.
Accompanied by his wife Michelle and their daughters Malia and Sasha, Mr Obama nodded and clapped along at the concert, which included Bruce Springsteen performing his song The Rising, Mary J Blige singing Lean on Me and James Taylor singing his hit Shower the People"
Beyonce, U2, Stevie Wonder, Usher and Sheryl Crow also performed at the concert.
Between the songs, actors Denzel Washington, Laura Linney and Tom Hanks gave speeches that evoked past crises in US history, including the Civil War, the Depression and the Cold War.
Sombre assessment in speech
In a speech at the concert, Mr Obama called for a new spirit of national sacrifice to overcome war and economic crisis.
"In the course of our history, only a handful of generations have been asked to confront challenges as serious as the ones we face right now. Our nation is at war. Our economy is in crisis," he said.
"I won't pretend that meeting any one of these challenges will be easy. It will take more than a month or a year, and it will likely take many.
"But never forget that the true character of our nation is revealed not during times of comfort and ease, but by the right we do when the moment is hard.
"I ask you to help me reveal that character once more, and together, we can carry forward as one nation, and one people, the legacy of our forefathers that we celebrate today."
No quick fix for economy
Top aides of Mr Obama gave TV interviews that emphasised his plans to quell the financial crisis that began in the US and has spread around the world.
The US unemployment rate rose to 7.2% in December, its highest level in nearly 16 years, and 2.6 million people have lost their jobs in the past year, the largest employment slump since 1945.
"These problems weren't made in a week or a year and they're not going to be fixed in a week or a month or a year," said Lawrence Summers, incoming director of the White House National Economic Council.
Mr Obama's inauguration takes place on Tuesday (US time).