For years, just enough hardcore classic car lovers and curious travellers wandered through the National Corvette Museum in Kentucky to keep the doors open. Now, after a massive sinkhole swallowed eight pristine models, attendance has skyrocketed.

Visitors are as eager to peer into the chasm as they are to see the ‘Vettes.

“The response to this has been bigger than anyone could have ever imagined,” said museum spokeswoman Katie Frassinelli.

“On the one hand, we don’t want to be known as the sinkhole museum but on the other hand, it’s bringing a lot of people that may not have otherwise come.”

When the earth opened in February, stunned museum officials first saw it as a devastating setback. The eight damaged cars, carrying a total value believed to exceed $US1 million ($A1.08 million), toppled like toys amid rocks, concrete and dirt.

But in the months since, business has shifted into overdrive. Since reopening after a one-day closure, attendance is up nearly 50 percent from the same period a year ago.

Museum memberships are also rising fast and sinkhole merchandising has started.

The museum say it’s shaping up as the biggest surge in its 20-year history.

It first set up a webcam that allowed people to follow the retrieval of the fallen cars, but seeing the bonanza, the museum now gives tourists a much closer look at the 12 metre wide, 18 metre deep hole.

The damaged cars are displayed in a nearby room.

Corvette owner Ron Fleenor, gazing at the crumpled cars, spoke about the bond between owners and the iconic sports car.

“They give you a special feeling,” he said. “All of it – the handling, the power and the looks from other people.”

Chevrolet has stepped forward to oversee restoration efforts and those cars deemed beyond repair will also remain on display.

What becomes of the giant hole is still undecided but it will remain open at least through the summer, including the museum’s 20th anniversary in late August, officials said.