The Obama Presidential Center opened on Thursday in Chicago. Former President Barack Obama spoke at the ceremony alongside other former presidents.
The $850 million center opened 3,437 days after Obama left office. It began its opening day with a land acknowledgment.
Former presidents Bill Clinton, George Bush, and Joe Biden attended the event. President Donald Trump was not present.
Obama said the founders fell terribly short of the Declaration of Independence by leaving slavery intact. He added that the Constitution provided a framework to make the union more perfect over time.
At the end of the ceremony, former President Joe Biden lingered on stage and asked where his granddaughter was seated in the audience.