Today marks the opening of 10 Hudson Yards, the first building in the 20-acre, roughly $20B complex to officially open.

Over the next few weeks, Coach will move about 1,400 workers into the 52-story building (at right in the rendering above). Coach, which paid $750M to buy and build out its 738k SF space, was the first office user to commit to any Hudson Yards building.

“It’s a realization moment, but it’s just the beginning," Related Cos chairman Stephen Ross told the Wall Street Journal.

Part of 10 Hudson Yards straddles a stretch of the High Line that will be dubbed “Coach Passage," signifying the fashion brand’s support for the elevated park.

“Until you start to do it, you don’t understand the magnitude of what you are taking on,” Stephen said. “You sit back, and you plow ahead.”

Firms including L’Oreal and Time Warner have committed to office leases at the mega-complex, which will total more than 17M SF when the last beams are bolted together. That’s on pace to happen by 2025.

Stephen tells the Journal that well over half of the development’s pipeline—about 9.5M SF—still needs to secure financing, which is a tall order in the current capital markets environment. But experts have said big-name developers—and Related Cos easily qualifies—will have the best chance of escaping unscathed. [WSJ]