WASHINGTON – More than 1 million people crammed onto the National Mall and along the inauguration parade route Tuesday to celebrate the swearing-in of the nation’s first black president in what was one of the largest-ever gatherings in the nation’s capital.

The Associated Press estimate is based on crowd photographs and comparisons with past events.

The crowd stretched nearly two miles to the steps of the Lincoln Memorial where Martin Luther King Jr. delivered his “I Have a Dream” speech.

The bulk of the crowd was jammed into the area between the west front of the Capitol and the Washington Monument.

Police had projected crowds ranging between 1 and 2 million for the inauguration.

Clark McPhail, a sociology professor at the University estimated the crowds could reach between 1.2 and 2.1 million, in an interview with the News Bureau before the inauguration. McPhail is an expert on crowds and their behavior.

“Many will come to this inauguration to praise the president, many others to protest or advocate on multiple issues, others to sell souvenirs, food and beverages, others to record and report, still others to protect,” McPhail said.

Some estimates for the crowds reached 4 million people before the event, yet McPhail said these numbers were unfounded.

“Estimates made from the front of the gathering and from a vantage point at or near ground level are victim to the perceptual illusion that the entire gathering is as densely packed throughout as it is at the front,” he said. “This leads to the erroneous conclusion that the gathering is much larger than it more accurately appears when viewed from overhead.”

Associated Press writers Brian Westley, Brett Zongker and Ben Nuckols in Washington and Dena Potter in Fredericksburg, Va., and Daily Illini assistant news editor Melissa Silverberg contributed to this report