President Obama and the first lady were joined by Hillary and Bill ClintonWilliam (Bill) Jefferson ClintonShould the Rob Porter outcome set the standard? Make the compromise: Ending chain migration is a small price to legalize Dreamers Assessing Trump's impeachment odds through a historic lens MORE on Thursday at the opening of a new museum dedicated to the Sept. 11, 2001, terrorist attacks.

The Obamas and Clintons toured the museum in New York City with a small group of survivors and victims' families.

The museum, which wraps through and under the Ground Zero site where the World Trade Center once stood, includes exhibitions devoted to the nearly 3,000 who died in the terror attack and artifacts from the fallen towers.

According to the museum, it houses more than 10,000 artifacts in 110,000 square feet of exhibition space. The museum has also collected nearly 2,000 oral histories from those touched by the tragedy.

The Obamas and Clintons were given a guided tour of the museum by former New York City Mayor Michael Bloomberg, according to a White House official.

They were expected to be joined by New York City Mayor Bill de Blasio as well as former Mayor Rudy Giuliani, who held office on the day of the attacks.

De Blasio has called on the federal government to help subsidize the museum, in a bid to open free access to the public. When the museum opens, tickets will cost $24 for adults, excepting active service members, victims’ families and those involved in the recovery effort.

The White House declined to weigh in on that request when asked on Wednesday.

“I haven’t heard discussion of that request or that observation by the mayor,” White House spokesman Jay Carney said Wednesday. “I think tomorrow the president and the first lady will be focused on the opening of the museum and all that it means to the people of New York, the people of the country.”

The museum, which costs an estimated $700 million, was funded primarily through private donations solicited by Bloomberg.

— This story was updated at 9:40 a.m.