All aboard!

After three decades of planning, building and dreaming, the train connecting downtown to Denver International Airport is finally opening for business, offering rides to the public for the first time at noon Friday.

The free rides, leaving Union Station and DIA, will continue until 9 p.m. Friday. They resume at 5 a.m. Saturday until 10 p.m. Regular fare service for the commuter rail line, costing $9 and lasting 37 minutes for a one-way ride, begins Sunday.

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The A-train’s maiden voyage, limited to members of the media, rolled out of Union Station at 5 a.m. Friday. The ride to DIA was noticeably smooth and quiet, with none of the track clatter often heard and felt on older commuter train systems in the United States.

Regional Transportation District general manager Dave Genova, along for the pre-dawn run, attributed the smooth ride to the line’s newness and to the fact that it doesn’t share track with heavy freight trains.

“We have brand new vehicles, we have brand new track, we have brand new infrastructure,” he said.

Colorado’s dignitaries — from Gov. John Hickenlooper to U.S. Sen. Michael Bennet to U.S. Rep. Diana DeGette — left Union Station at 8 a.m. for a ride out to DIA. They, along with acting administrator of the Federal Transportation Administration Carolyn Flowers, gave speeches during a ribbon-cutting ceremony at the airport.

Denver Mayor Michael Hancock, who took the early train Friday, was at the Union Station platform before the sun came up. He said the line will be “huge” for the region and raising its profile.

“This is a big deal,” Hancock said. “Today, we’re caught up and we’re saying to the rest of the world, ‘we’re coming.’ ”

Denver City Councilman Kevin Flynn has a unique perspective on the unveiling. He covered the initial push to bring a train to DIA as a reporter with the Rocky Mountain News, then was a RTD spokesman for the FasTracks commuter rail project. He won the District 2 seat in in 2015.

“I covered the entire process and it took 30 years,” Flynn said. “Fifty years from now, people will think we did it seamlessly. They will think it was way easy. It was not easy.”

Kim Day, DIA’s chief executive officer, called the inaugural ride “a thrill.” She said not only will the flying public benefit from the new rail line, but so will the 35,000 people who work on the airport property.

“This is a new commuting tool for these people,” she said.

Day said she has scouted out a parking space for herself at the 38th and Blake Street station for her daily trip to her office at DIA.

“I live downtown — this is my new commute,” she said.

One of the most welcome conveniences travelers will find right off the DIA A-train platform are half a dozen kiosks where they can print out boarding passes. There is also a bag drop, where they can hand off their bags — including skis and golf clubs — and skip having to go to the check-in counter upstairs.

Meaning the only thing ahead of them before their flight is a four-story escalator ride straight to the security line.

“You get off the train, go up the escalator and you’re 50 feet from security,” Day said.

The bag drop, Day said, is expected to be operational starting Sunday. To start, United, Delta, Southwest and American airlines will be participating though other airlines are expected to offer the service once they integrate their baggage systems into it, she said.

The bag drop will be run by concessionaire Bags Inc.

The $1.2 billion University of Colorado A-Line, the first commuter rail line in Colorado, is the culmination of a plan hatched approximately 30 years ago, when the idea arose of moving Denver’s airport from its old Stapleton location to a new site on the outskirts of the city.

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It took 15 years for voters to give their blessing to the airport line with a yes vote on the 2004 FasTracks initiative, which promised 122 miles of new rail and 18 miles of bus rapid transit throughout the metro area.

Groundbreaking for the 23-mile line to DIA, with six stops along the way, occurred in 2010.

Day told The Denver Post last week that the new line places the airport shoulder to shoulder with some of the premier airports in the world.

“The addition of the commuter rail will no doubt elevate our status among the global cities that offer this type of connectivity to their airports,” she said. “This means that we are no longer competing with Dallas and Chicago, but we are now competing with Zurich and Paris and other international airports.”

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When regular pay service begins Sunday, the A train will run every 15 minutes between 6 a.m. and 8 p.m. and every 30 minutes at other times, with the first train departing Union Station at 3:15 a.m. and the final train leaving DIA at 1:26 a.m. on weekdays.

RTD spokeswoman Tara Bettale said travelers should allow plenty of extra time if they are using the line to catch a flight Friday and Saturday, given the crowds that are expected to show up for the line’s debut and the delays that may cause.

RTD tweeted an update Friday morning that those who are flying out to “Please use SkyRide to get to DIA on time.”

She said service should take on an air of normalcy after the fare-free rides conclude Saturday night.

John Aguilar: 303-954-1695, jaguilar@denverpost.com or @abuvthefold