Sarah Craighead stands in 2017 on the historic trail in Mammoth Cave.

Mammoth Cave National Park commemorated the National Day of Service and its longtime partnership with the Cave Research Foundation on Saturday by announcing the cave system is now officially eight miles longer.

The additional mileage was mapped and documented through survey work completed by the CRF. The discovery brings the official length of the world’s longest cave to 420 miles.

Jessica Cooper, the park’s acting public information officer, said the CRF has worked to map the system every year.

Cooper said a description of the new passageways could not be provided as of Monday afternoon.

“It’s very important to know as much about the resource as we can in order to protect it for future generations,” she said. “The more we understand about the cave, the more equipped and prepared we are to ensure the preservation of those resources. We are very thankful for our volunteer partnerships and organizations.”

The CRF is a local nonprofit group founded in 1957. CRF members spend hours crawling, climbing and rappelling through cave passageways, following leads through sometimes very tight openings to document and map the cave.

Comprised exclusively of volunteers, the group has assisted the park with cave survey work for more than 60 years and has provided thousands of hours of volunteer work.

“The Cave Research Foundation is fundamentally the reason that Mammoth Cave is recognized as the world’s longest cave,” Cave Resource Management Specialist Dr. Rick Toomey said in a statement. “Without CRF exploration and mapping, Mammoth Cave would potentially still be a 44-mile-long cave system.”

Mammoth Cave received its official designation as the world’s longest cave system in 1969 with 65 miles of surveyed passageways.

The connection between the Mammoth Cave system and the Flint Ridge system was discovered in 1972 by CRF cavers who traveled underground for more than 14 hours.

This connection would bring the total mileage of the Mammoth Cave system to 144 miles.

In the 49 years since this connection was made, continued assistance from the CRF has led to discovered connections between several smaller caves like Proctor Cave, Roppel Cave and Morrison Cave and the larger Mammoth Cave system, all contributing to the current total surveyed length of 420 miles.

Cooper said the park received a large reaction across social media over the weekend when park officials posted about the discovery.

“People are always curious how much cave is really beneath their feet,” Cooper added. “We have had a really good response on Facebook from around the world – not just from this area. With this discovery, it’s one way for us to reach another generation of cave enthusiasts and national park enthusiasts. Social media is a way to attract younger people to national parks, and this discovery will attract those people in the future.”

A variety of opportunities to volunteer for the National Park Service exists for interested parties.

While some volunteer positions require certain skills or abilities, others require no specialized training. For more information about the Volunteer-In-Park program, visit www.nps.gov/getinvolved/volunteer.htm.

– Follow reporter John Reecer on Twitter @JReecerBGDN or visit bgdailynews.com.