The Board of the National September 11 Memorial and Museum has approved a motion to charge a mandatory entrance fee to the underground Memorial Museum when it opens next year, sparking public outrage from prospective visitors.

According to Museum officials, who have reportedly received over $425 million from state and federal governments as well as $450 million in private donations thus far to build the $700 million attraction, they will need to charge a fee of $20-$25 per person to cover operating costs. The New York Daily News reports that annual operating costs will run the foundation approximately $60 million.

"As a nonprofit organization that relies on the support of the public, not city, state or federal funding for our operations, we are charging an admission fee in line with other comparable institutions," said spokesman Michael Frazier.

However, when the general public got wind of the moderately pricey entrance fee reactions ranged from dismay to shock to anger and everything in between.

"It's not fair at all," Joseph Shi of Flushing, Queens told the New York Daily News. "It's not like a normal museum. It's different."

Retired FDNY Deputy Chief Jim Riches, who lost a son in the 9/11 attacks told NY1 that he is outraged.

"It's becoming a real commercial enterprise and it looks like that," Riches said. "We think it's disgusting and revolting. If they had a suggested donation I think all Americans would be very patriotic."

Debra Burlingame, who took part in planning the museum told Gothamist "the idea of charging admission is not something we ever wanted to do. [But] I don't think people realize the enormous costs of building something like this, in a location like this."

According to the 911 Memorial Web site, the Memorial Museum will serve as the country's principal institution for examining the implications of the events of 9/11, documenting the impact of those events and exploring the continuing significance of September 11, 2001.

The museum will have 110,000 square feet of exhibition space within the heart of the World Trade Center site. It seeks to tell the story of 9/11 through multimedia displays, archives, narratives and a collection of authentic artifacts.

"In remembering the victims of the attacks and honoring those who went to their rescue, the Museum will explore the very real impact of terrorism in the lives of very real people, and their families, friends, colleagues and communities," said Alice Greenwald, Director of the Memorial Museum. "As custodian of memory, the Museum will take on the mantle of moral authority that will define its continuing and evolving role. This Museum will do nothing less than underscore the absolute illegitimacy of indiscriminate murder."