New York City is not known for having a lot of extra space. So good things sometimes happen in odd places. That's why the High Line park, built on an old elevated train platform in the Meatpacking district of Manhattan's West Side, became such a hit.

And now a variation on unused space may get the park treatment as well. But this time it's underground.

The founders of the park plan, architect James Ramsey and Dan Barasch, have built a full-scale model of what they're calling the Lowline, a park in an abandoned subway station below Delancey Street. To give New Yorkers a sense of what a subterranean play area would be like, the co-founders raised $155,000 so New Yorkers could try it out.

The exhibit of the potential park is in a warehouse in the Lower East Side through Sept. 27.

Watch a slideshow of the proposed underground park.

Visitors can explore the plan for an abandoned Delancey Street train station on the Lower East Side to be transformed into green space.

As the co-creators say in their Kickstarter video used to raise funds for their park exhibit, Ramsey's office is not far from the defunct trolley terminal, their proposed site. The underground space, built in 1903, hasn't been touched since 1948 and includes details such as granite cobblestones, rail tracks and vaulted ceilings.

Because the park would be indoors, lighting becomes an obvious challenge. To get around that, the park co-creators invented a technology to bring natural light underground. The technology, called a "remote skylight," captures natural sunlight from the surface and then channels it underground through fiber-optic cable, generating enough light to grow plants, trees and grass, even underground.

The park presentation shows a lush oasis below ground. Horticulturalist Misty Gonzaliez told DNA Info that she chose plants native to Asia, including a Japanese maple, mood moss and mushrooms.

In an emailed statement to Yahoo News, Lowline Co-ounder Dan Barasch noted, "We think the Lowline represents a fresh way to re-imagine the meaning of public space, the possibilities of solar technology, and the power of mixing history with cutting-edge design. New York has always been short on public spaces, but a new generation of urban renewal is reclaiming our waterfronts, our rooftops, and our abandoned railways for public use. It's inspiring to be a part of that movement, in New York City and around the world."