Monday is a historic day in the nation's capitol. Organizers are expecting 700,000 people to attend today's events, which would make it the largest second-term inaugural in history.
Spectators look to see history, whether or not they backed Obama. Spectators heading to Monday's events are facing tight security. Screening lines in some places stretched a block.
Humvees and city buses are being used to block intersections. Volunteers have fanned out near the Mall to help direct crowds.
It is a historic day for sure. All inaugurals have been historic. That they have in common.
But they have been also so different as the world has changed so much over the course of time. Let's take a look at how much they have changed.
Here are some inauguration facts:
• George Washington's was the shortest inaugural address at 135 words. (1793)
• Thomas Jefferson was the only president to walk to and from his inaugural. He was also the first to be inaugurated at the Capitol. (1801)
• The first inaugural ball was held for James Madison. (1809)
• John Quincy Adams was the first president sworn in wearing long trousers. (1825)
• Franklin Pierce was the first president to affirm rather than swear the oath of office (1853). Herbert Hoover followed suit in 1929.
• William H. Harrison's was the longest inaugural address at 8,445 words. (1841)
• The first inauguration to be photographed was James Buchanan's. (1857)
• Abraham Lincoln was the first to include African-Americans in his parade. (1865)
• James Garfield's mother was the first to attend her son's inauguration. (1881)
• William McKinley's inauguration was the first ceremony to be recorded by a motion picture camera. (1897)
• William Taft's wife was the first one to accompany her husband in the procession from the Capitol to the White House. (1909)
• Women were included for the first time in Woodrow Wilson's second inaugural parade. (1917)
• Warren G. Harding was the first president to ride to and from his inaugural in an automobile. (1921)
• Harry Truman's was the first to be televised. (1949)
• Lyndon Johnson was the first (and so far) only president to be sworn in by a woman, U.S. District Judge Sarah T. Hughes. (1963)
• Jimmy Carter's inaugural parade featured solar heat for the reviewing stand and handicap-accessible viewing. (1977)
• Ronald Reagan's second inaugural had to compete with Super Bowl Sunday. (1985)
• The first ceremony broadcast on the Internet was Bill Clinton's second inauguration. (1997)