With over 8 million people crammed into just a few hundred square miles of island, New York City has few places left untouched and even fewer places for new parks. If two guys who boast Yale, Cornell, NASA and Google on their resumes get their way, though, people may soon go to what is thought of as the darkest of places to enjoy a little sun and greenery: underground. James Ramsey and Dan Barasch have proposed converting a trolley terminal that hasn't been in use in more than 60 years into an underground park filled with grass, trees and a few new local shops, reports the New York Times. The park and its accompanying greenery would be possible because of fiber optics that collect sunlight and send it underground. The developers are unsure of the project's exact costs at this point, but have met with the local transportation authority, which owns the property and likes the idea but wants to make sure that the project would bring in extra money for the city. The developers call the project the "Delancey Underground" because it sits below Delancey Street, but many refer to it as the "Low Line" -- in contrast to the city's popular High Line that once was an abandoned railroad.