New York City's Penn Station, long denigrated as ugly, congested and confusing, has a flashy new addition that could provide a glimpse of its future.

Officials on Thursday opened a new, $300 million concourse across the street from the aging rail station that will give passengers easier access to 17 of the 21 train platforms used by Long Island Rail Road, New Jersey Transit and Amtrak trains.

On its first day, the hall, unlike its sister facility across the street, was gleamingly clean, brightly lit and pleasant.

Digital panels on the ceiling created the image of a blue sky and passing clouds. Large windows allowed commuters to see the trains on the platforms below.

The concourse is the first phase of a plan to convert Manhattan's massive main post office into the Daniel Patrick Moynihan Train Hall, named for the late Democratic U.S. senator from New York who first proposed the project many years ago.

"It's beautiful," Lynne Watson, of Queens, told Newsday after heading down from her customer service job at the post office to take a look. "It makes it seem bright. You come through Penn Station and it's kind of dark down there."

The new entrances to the rail platforms will help ease the chokepoints that develop in Penn Station during rush hours, as too many commuters try to jam down too few stairwells and escalators.

By 2020, much of the post office is slated to become a grand new, $1.6 billion west wing of the station, replete with a dramatic glass roof, new retail and office space.