WASHINGTON (AP) -- When the Smithsonian Museum of African-American History and Culture opens this week alongside the Washington Monument and the National Museum of American History, it will firmly -- and finally --anchor the black experience in the nation’s narrative.

“In 1915 … they say, ‘There should be a monument. There should be a memorial that honors our contribution,’” said Michelle Wilkinson, one of the museum’s curators. “Not just a pile of stone, or a shaft. It needs to be a museum.”

Fifty years after the end of the Civil War, black citizens in Washington, D.C., formed the National Memorial Association with the purpose of “erecting a beautiful building … suitable to depict the Negro’s contribution to America.” It would be, they said, “a shrine for posterity.”

It has taken a century for their dream to be realized in Washington, a place visited by more than 20 million people from around the world who want to learn about the United States. During that time, other monuments and museums celebrating the stories of other Americans were proposed and built in the nation’s capital.

On Saturday, the long wait is over: America’s first black president and first lady will preside over the museum’s opening.

Thousands are expected to attend the museum’s inaugural weekend, and millions more will virtually experience the milestone via social media.

The imposing space on the National Mall likely will set visitor records. And in an era informed simultaneously by the historic election of President Barack Obama and a succession of killings of unarmed black men at the hands of police, it is a building that will affirm for many that black lives matter.

Its facade is unlike anything else in Washington. The building’s outward design -- known as the Corona -- features walls reaching skyward, evoking the resiliency, faith and hope that has sustained black Americans since they were brought to the country in bondage. Its three-tiered shape is inspired by a symbol from the Yoruba people of West Africa featuring a crown. The 3,600 bronze-colored panels surrounding the building are a tribute to the 19th-century ironwork created by slaves in New Orleans.

“The structure itself is imbued with meaning,” said Phil Freelon, the lead architect for the museum. “All these things are subtle. That’s intentional. It has a certain sense to it that is African-American, in the way that our culture is expressive in other areas. We believe architecture can evoke those sorts of emotions.”

It is a building that fulfills the original vision of the association members. In a letter addressed to state representatives across the country, the group pled their case for a national memorial, saying, “General memorials do not make the average American think of Negroes. Therefore, the failure to erect a special memorial may and probably will be interpreted as meaning that Negroes have made no great contribution to American advancement in war or in any other field.”

They went on to say: “It would be a splendid idea if all this could find a place in a public building in Washington where it would reflect the greatest possible good throughout the country.”

Washingtonians have watched the building rise from nothing on a grassy knoll at the bustling intersection of Constitution Avenue and 15th Street. Construction on the museum began in 2012, the same year Obama was re-elected to a second term. It will open four months before he is set to leave office. 

Standing five stories high with 60 percent of the building below ground, the 400,000-square foot structure attempts to hold four centuries of black history. Visitors begin by descending to the basement and then walk up a series of ramps winding through the origins of slavery, to the bonds of Jim Crow, to an integrated society. Exhibits on the upper floors highlight the unique contributions of blacks to areas of American life, including the military, sports, music, the visual arts, film and television, business, the news media and religion.

Artifacts large and small fill the space, sure to evoke feelings of pain and pride from the collective memories of black visitors.

There are the ankle shackles that would have been used to restrain people who became slaves after crossing the Atlantic Ocean from the African continent to the Americas. A bill of sale for an enslaved 16-year-old girl named Polly, who was sold for $600 in Arkansas in 1835. A segregated Southern Railway passenger car that would have passed through Kentucky, Tennessee, Georgia and Florida. Glass shards and shotgun shells from the 16th Street Baptist Church in Birmingham, Alabama, where four little girls were killed in a racist bombing in 1963.

There also is a biplane used at Alabama’s Tuskegee Institute to train black pilots for Army Air Corps service during World War II. A vintage red Cadillac from rock-and-roll legend Chuck Berry’s personal collection. Harriet Tubman’s hymn book, circa 1876. Michael Jackson’s fedora.

Visitors can eat at a cafe featuring authentic black cuisines from four regions of the country: the agricultural South, the Creole coast, the North states, and the Western range. Dishes include Brunswick stew, shrimp and grits, an oyster pan roast, and rainbow trout stuffed with mustard greens.

Marcia Morris, a 12th-grade English teacher who lives in nearby Fairfax, Virginia, has closely followed news reports as the museum acquired rare treasures and opening day approached. “The closer it came to completion, the more real it became,” she said.

As construction progressed, Morris thought often of her deceased grandparents, who lived during segregation.

“A museum just dedicated to the history of black people? That was not in the realm of (my grandfather’s) thought process,” she said. “They weren’t educated. I know the things my grandparents went through. I think we owe something to that generation.”

Tickets to the museum are free, but visitors must make reservations for timed tours. Weekends already are booked through early December, and the museum has extended its hours to accommodate the increased demand.

Morris ordered tickets next month to coincide with her daughter’s 16th birthday, which she finds a fitting way to mark the occasion.

“They have a black president, people on television are black, black is cool to them and their friends,” Morris said of her daughter and son. “I don’t want them to ever not know what black people have gone through.”

When Dianne Washington travels south from Harlem to visit the museum at the end of October, she said will be making a trip that is overdue.

“We have contributed so much to this country, free of charge,” she said.

She is overjoyed that the moment is finally here.

“Everything was built on our backs,” she said. “Our ancestors suffered so much. Something should be in place to honor them and their story told properly. Why not us? I can’t wait.”