One day after their star-studded grand opening ceremony, it appears the Obamas weren’t done celebrating in Chicago.

Former President Barack Obama and former First Lady Michelle Obama surprised guests in line for the official Juneteenth public opening of the new Obama Presidential Center on the city’s South Side.

The pair greeted the first 100 entrants into the center Friday, taking photos, shaking hands and talking to those who came from near and far to visit the new facility.

Watch the moment below:

It was a special day for those in attendance.

"This is just so amazing. It is truly amazing that this can happen, especially for our culture," visitor Natasha O’Neil told NBC Chicago.

"We did get married on the 19th and it is Juneteenth and it’s 44 years and the 44th president. So we’re like, ‘Oh, so it’s really exciting,’" visitor Paul Cribb said.

While those in line on Friday were some of the many planning to visit the center in the coming months, those who don’t already have a ticket might not have such luck.

Tickets for the public opening of the sprawling center, taking place on Juneteenth, are sold out and have been for months. Earlier this week, the venue’s ticketing website showed admission was booked through November, with only 17 dates available.

Friday morning, it appeared the center was completely sold out for all future dates until new tickets are released.

"Sorry, tickets are not available for this event," a message on the Obama Presidential Center’s ticketing website said. "Join our mailing list to get the latest news on the Obama Presidential Center and find out when new tickets are released."

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The museum previously said timed-entry tickets were available through Nov. 30.

"Check weekdays and fall dates for best availability," it said.

Tickets to the center include access to all four levels for the museum, the Oval Office replica and the Sky Room, organizers said. The center said it will also have Illinois Free Days on Tuesday, but tickets must be reserved in advance.

It wasn’t immediately clear when tickets would become available again.