The city’s police department is set to get a new $1 billion training academy in Queens to replace its dated and cramped facility, which opened when President Johnson was in the White House.

The new site, on which the city is aiming to break ground in 2009, will be a state-of-the-art, college-style campus that will include a mock streetscape and subway platform for terrorism drills, a firing range, and dozens of other facilities.

Mayor Bloomberg referred to the planned 30-acre site as a “single public safety campus,” and said one of its biggest virtues will be its capacity to consolidate the academy’s three main programs under one roof. For years, they have been scattered across three boroughs, requiring teachers and cadets to commute a triangle of roadways.

“We estimate that building a new training campus will cost over $1 billion,” Mr. Bloomberg said. “Now, that sounds like a lot of money, but this is a smart and essential investment.”

In addition to high-tech wireless classrooms and a capacity to broadcast lessons to 5,000 people at once, the new facility will also have about 250 beds. That, Mr. Bloomberg said, will allow the NYPD to run the side business of bringing in law enforcement departments from other parts of the country and world for training courses.

“When people around that world talk about a police department, the ultimate example is the NYPD and that is something we should share,” Mr. Bloomberg said. “It’s something the city really has of great value and we should be training others and charging them for it. I think there would be a big market for that.”

Mr. Bloomberg first announced his plan to move the police academy in January. Yesterday, he said the city had chosen to build it in College Point, Queens, at a site that is now home to a sprawling, city-owned police department tow pound. A selection committee chose the location from a short list that included eight options, including the abandoned Flushing Airport, a piece of land adjacent to the Aqueduct Racetrack, and a Staten Island site once slated for a prison.

The existing academy is located on 20th Street in the densely populated Gramercy section of Manhattan, meaning it’s been boxed in with no room to grow. Because it was designed for a police force half the size of today’s, trainees must trek to a shooting range 25 miles away in the Bronx and to a another training site in southeast Brooklyn.

“The beauty of this is that it’s all going to be in one location,” Commissioner Raymond Kelly said.

Mr. Kelly said the new site would train classes of 2,000 cadets at a time and graduate 4,000 a year. That represents a major upgrade from the current system, where the academy squeezes in rotations of cadets on nights and weekends.

According to Mr. Kelly, the Commission on National Law Enforcement Accreditation Agencies recently praised the police department’s programs, but said it had inadequate classrooms, far-flung training facilities, and outdated heating and cooling systems.

Mr. Kelly said that because there is no track, cadets use the path along the FDR Drive to run. The department also had to divide the men’s locker room when women started joining the force.

Mr. Bloomberg will be including the project (which city officials say will cost a minimum of $1 billion) in his capital budget plan and will issue bonds to pay for it. The project is one of the administration’s most expensive, and if construction starts by 2009, as the mayor has said, it would slip in as one of his last major legacy-shaping initiatives.

The Manhattan academy, which is on a prime piece of real estate, would likely be sold, a transaction that could yield the city a pretty penny. That wouldn’t happen for a while because the city still needs to win approval through the land-use process, design the site, and build it.

“At the moment the real estate market for East 20th Street is a pretty hot market,” the mayor said. “But we’re talking about a long time.”