The series "Night Visions" had a neat story about a college girl who enters a campus maze and comes out in another time frame a few years later, where no one is around. She eventually meets a guy she knew in "the old days" and he and the rest of the world are waiting for a comet/asteroid to arrive that will wipe out the world. Then the warning siren goes off.
"The Maze"
I thought the college buildings were an architectural marvel - somewhere up in Canada, I think.