Hollywood superstars Tom Cruise, John Travolta and Kelly Preston were reportedly among the thousands of Scientologists gathered Sunday in Clearwater, Fla., to dedicate the Flag Building, a multi-million dollar addition to the church's headquarters there.

The 377,-000-square-foot building, which cost $145 million to build, is the only one of the church's facilities to have special rooms for practicing the "Super Power" program designed by Scientology's founder L. Ron Hubbard. The church has been waiting since the 1970s, when Hubbard developed the program, to have a proper venue to unveil it, according to the Tampa Bay Times.

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The program is designed to develop what Hubbard described as human beings' 57 senses, or "perceptics."

"Hubbard said that the 'Super Power" program will develop Scientologists, [giving them] new skills, new abilities to perceive and new levels of awareness," Joe Childs, the Times' senior editor-at-large, told ABC News. "[That] it'll position Scientologists to take a lead, he said, in leading the world out of social decay [and] saving mankind."

Only Scientologists, such as Cruise, Travolta and Preston, were allowed inside the building after an eight-minute dedication ceremony led by church leader David Miscavige. The ceremony was kept strictly private by hundreds of church volunteers who policed the building's perimeter to keep onlookers, including the media, out.

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A graphic animation on the church's website shows the building includes an atrium, bookstore and chapel, but church officials have declined to release any additional details and have not said when, or if, the building will be open to non-Scientologists.

Documents submitted to the city of Clearwater also show the building includes a dining facility, offices, course rooms and hundreds of small rooms for "auditing," the Tampa Bay Times reports.

Renderings of the building leaked to the Village Voice newspaper in 2012 show that among the new tools for Scientologists are a motion quadrant that will reportedly spin you like a gyroscope to improve your perception of compass direction, and a tool that will reportedly check your magnetic sense.

"On the fifth floor are some machines that Scientology says can help develop [the] sense of smell, taste, awareness and … balance," said Childs.

The Church of Scientology did not respond to ABC News' request for comment.