Martin Luther King Jr. Day is a national holiday Monday, January 16.
In St. Louis, the three-day weekend means it's free admission to the Gateway Arch on the Mississippi River, January 14-16.
The National Parks Service has free admission days several times a year at many of its parks and monuments.
On the other hand, K-Mart has taken the occasion to have blow-out sales during MLK Day holiday celebrations—online only. (See photo)
King's leadership in non-violent civil disobedience resulted in key U.S. civil rights legislation during the mid-1960s, signed by then-President Lyndon Johnson—but not without the loss of King's life.
King, 39, was asassinated in 1968, on a Memphis motel balcony as he prepared to meet with a union of striking public sanitary workers.
"I've seen the promised land. I may not get there with you," King said during his last speech known as I've Been to the Mountaintop.
"But I want you to know tonight, that we, as a people, will get to the promised land," King said.
King's 1963 speech, I Have A Dream, described his four young children living in a nation where they would be judged by the content of their character, not the color of their skin.
King won the Nobel Peace Prize in 1964 for his work. He was a Baptist minister, and the son of a minister. King started college at 15, earned two bachelor degrees, a Ph.d. in theology, and was the author of several books.
In related news: Developers of a new 30-foot high stone monument to King on the Mall in Washington, D.C., face controversy over the inscription of an edited quote of King's, related to his Drum Major sermon a month before his death.