As onerous as it is to pay rent on an unused space, the millions that Six Flags is spending on the park represents a small fraction of its problems. Its biggest concern is a looming $287.5 million debt it must pay by August 15. Six Flags has been delisted from the New York Stock Exchange, and is trying to structure a debt-for-equity deal.

But Six Flags is fighting harder than ever to preserve its core business. This summer the chain will debut new attractions at almost all of its parks. It's expanded its operating calendar and is experimenting with broader food options. Most importantly, it's invested roughly $100 million in maintenance to address customer complaints thatit s properties were getting seedy.

But Six Flags's overriding concern -- getting customers into the parks -- is driving ticket discounts on daily admission, and it's selling season passes for the lowest price in 10 years. The move is intended as a bargain-priced alternative to destination parks like Disney World. With 20 properties in the U.S., Mexico, and Canada, the chain's key strength is to offer a solid staycation option, often free of the cost of airlines and hotels.

The strategy paid off last year, when many Six Flags parks saw record attendance. On Memorial Day last month, Great America, the company's most profitable attraction, had 25,000 visitors, more than doubling corporate expectations. Even if the company must declare bankruptcy, CEO Mark Shapiro says its daily operations will not be affected and characterizes a possible reorganization as a "back-of-the-house issue." Still, the company is keeping its seatbelt fastened for more thrills and chills.

See more iconic American companies on the brink.