A massive sinkhole that swallowed eight cars at the US National Corvette Museum in Kentucky has become such a popular attraction that officials want to preserve it. They may even put some of the crumpled cars back inside the hole.

The museum's board has voted to preserve a large section of the hole that appeared in February, causing exhibits to cascade into the ground like toys, along with rocks, concrete and soil.

The cars, whose total value is believed to exceed $1m, include a 1962 black Corvette, a 1984 PPG Pace Car, a 1992 White 1 Millionth Corvette and a 1993 Ruby Red 40th Anniversary Corvette. They were eventually pulled out of the hole to great fanfare.

Officials say attendance is up nearly 60% from March to the start of this week, and the museum, which in previous years had struggled to keep its doors open, now sells sinkhole-related shirts, postcards and prints.

Sinkholes are common in the area, which is located in an extensive region of karst bedrock where many of Kentucky's largest caves can be found.