Nation’s Shortest Car Ferry Travels Just 200 Feet in a National Park

The Green River Ferry shuttles cars in a 30-second trip.

1 minute read

March 20, 2026, 5:00 AM PDT

By Diana Ionescu @aworkoffiction


Small ferry carrying two cars across small river in Mammoth Cave National Park, Kentucky.

The Green River Ferry can carry two vehicles across at a time. | Kelly vanDellen / Shutterstock

A nearly century-old ferry that shuttles cars across the Green River in Mammoth Cave National Park is the nation’s shortest, with the crossing spanning just 200 feet for a roughly 30-second trip.

As Brian Silvestro explains in The Autopian, “The boat, a single-engine barge, transports about 135,000 vehicles and 270,000 passengers a year. Drivers have to come up to the crossing, drive onto the boat, and take a 30-second ride across the water.” 

The ferry, established in 1934, operates 364 days a year and can accommodate two cars at a time — too few at times when close to 30 cars can stack up waiting to cross. The National Park Service restored and upgraded the ferry last year for $3.9 million, far less than the $50 million it would cost to build a bridge at the same location. The ferry also serves locals who need to travel through the area. 

Wednesday, March 18, 2026 in The Autopian

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