Leaving Berry Springs Lodge B&B on April 27 with a full charge—thanks to the Destination Charger we enjoyed during our visit to Great Smoky Mountains—we headed west and north through Tennessee to Kentucky and the next stop on our electric road trip to all 51 National Parks in the Lower 48 states, Mammoth Cave.
Mammoth Cave National Park was authorized in 1926 but was not formally established until 1941. It enjoys about 600,000 annual visitors.
Before our visit, we kept forgetting whether the name is Mammoth Cave or Mammoth Caves. After visiting the park, it’s now easy to remember, after learning from the exhibits at the Visitor Center and the Ranger-led tours that the cave system is one massive—or mammoth—interconnected series of tunnels.
Mammoth Cave is one massive—or mammoth—interconnected series of tunnels. To date, about 420 miles of the cave have been explored and mapped.
To date, about 420 miles of the cave have been explored and mapped. Experts estimate there could be another 600 miles yet to be explored.
In addition to the massive cave system, the park includes 586,000 acres of land on the surface.
Mammoth Cave is the result of some unique geological history in the region.
Mammoth Cave is the result of some unique geological history in the region. More than 300 million years ago, when the Earth had a single supercontinent called Pangaea, the area that is now central Kentucky was a large shallow sea, resulting in the formation of a layer of limestone about 400 feet in depth. Later, as the Appalachian Mountains formed, rivers running from the mountains deposited layers of soil and sand, creating a capstone layer of sandstone over millions of years. Over the last few million years, sinks have formed in the region, channeling water through cracks in the sandstone, and the underground sources of the Green River, which runs through the area, have carved interconnected tunnels in the limestone.
The Rangers at the park like to say that Mammoth Cave is “the Grand Canyon with a roof.”
The sandstone layer on top resulted in a cave structure rather than a canyon, as typically occurred in other areas where rivers flow through limestone. In fact, the Rangers at the park like to say that Mammoth Cave is “the Grand Canyon with a roof.”
The trails around the Visitor Center give a good in-person appreciation for the how the layers of sandstone and limestone, together with the sinks that channel water through the tunnels, resulted in the formation of such a massive cave.
The activities during our visit were well sequenced to appreciate the cave system and its origins. As always, we started our visit with a tour of the nice new, solar-powered visitor center and its excellent exhibits, which explain the geological history. We then spent the rest of the afternoon hiking 4 miles of the trails around the center. Those give a good in-person appreciation for the how the layers of sandstone and limestone, together with the sinks that channel water through the tunnels, have resulted in the formation of such a massive cave.
Various sources had recommended two particular cave tours—the Extended Historic Tour and the Domes and Dripstone Tour. Our experience was that both of those were great tours—and a good combination to appreciate the cave in two very different ways.
The next morning, we traveled back from Bowling Green for a full day, with plenty of time for two cave tours, which we had reserved in advance through the National Park Service ticketing system, Recreation.gov. Various sources had recommended two particular cave tours—the Extended Historic Tour and the Domes and Dripstone Tour. Our experience was that both of those were great tours—and a good combination to appreciate the cave in two very different ways.
We started in the morning of our full day at the park with the Domes and Dripstones Tour. This tour enters through one of the man-made entrances to the cave—an entrance that was initially built as part of a private for-profit enterprise prior to the establishment of the park. The tour is led by a Ranger and includes a ride in a bus for a few minutes from the Visitor Center to the entrance.
The Domes and Dripstones Tour, about two hours in duration and relatively short in distance at less than a mile, starts with a series of steel stairs down about 300 feet.
The Domes and Dripstones Tour, about two hours in duration and relatively short in distance at less than a mile, starts with a series of steel stairs down about 300 feet. One of the initial stops is a large amphitheater deep underground where the Ranger provides information about the cave and then turns the lights off to show what total darkness “looks” like. The tour traverses several domes and ends with some spectacular formations, including Frozen Niagara. This area of Mammoth Cave is quite wet, which results in the formation of such stalactites and stalagmites. The tour ends with a relatively gradual return to the surface, emerging at a different exit.
Lunch options between morning and afternoon tours are relatively limited. There is a lunch shack in a temporary building near the Visitor Center. We decided to try the local restaurants at Cave City and Park City, which are on Interstate 65 a few miles from the park. After driving through each town, we were disappointed in the options and decided to head back to the park for a burger at the snack bar.
The Historic Tour enters through the Natural Entrance, which is a short walk down from the Visitor Center. And as the name also implies, there is a lot of interesting history with the Extended Tour.
In the afternoon, we took our second tour of Mammoth Cave, the Extended Historic Tour. As the name implies, this is similar to the Historic Tour, but a little longer. The Historic Tour enters through the Natural Entrance, which is a short walk down from the Visitor Center. And as the name also implies, there is a lot of interesting history with the Extended Tour.
In contrast to the Domes and Dripstones Tour, the Historic Tour traverses a very old and dry section of Mammoth Cave. The entrance is a huge cave opening, and after passing through a security gate, visitors enter a series of massive tunnels. It is difficult to describe the scale of these tunnels, but the two thoughts that kept going through my mind were that we were in some kind of a prehistoric subway system or on the location of an Indiana Jones movie.
The Historic Tour proceeds rapidly through some massive tunnels, which helps to convey the enormity of the cave system. Along the way, there is much history.
The Historic Tour proceeds rapidly through these tunnels, which helps to convey the enormity of the cave system. Along the way, there is much history, including evidence of early activity by Native Americans. In the initial sections of the cave the tour passes the well-preserved remains of leaching pits used during the War of 1812 to process saltpeter for gunpowder. Later, the tour passes out-of-place stone houses that were used for a few years to house people suffering from tuberculosis, in an ill-founded experiment to see if living in the cave could provide an effective treatment.
Toward the end of the tour, which lasts about 2-1/4 hours, visitors pass through much narrower sections of the cave, including passages called by the self-explanatory names of Fat Man’s Misery and Tall Man’s Misery.
The 2-1/2 miles of the Extended Historic Tour do a great job of conveying the vastness of Mammoth Cave and is a great combination with the different experience offered by the Domes and Dripstones Tour.
In all, the 2-1/2 miles of the Extended Historic Tour do a great job of conveying the vastness of Mammoth Cave and is a great combination with the different experience offered by the Domes and Dripstones Tour.
Lodging
Bowling Green, Kentucky, is the place to stay when visiting Mammoth Cave. It is a very pleasant small city, home to Bowling Green State University. Although it is about a half-hour drive to the park, there are no good options closer to the park, and visits are typically only one day, so you don’t have to make the trip multiple times.
Bowling Green, Kentucky, is the place to stay when visiting Mammoth Cave.
We stayed at the Courtyard by Marriott Bowling Green Convention Center, which has four Destination Chargers in the back of the hotel. We were very pleased with this hotel, which is a modern facility with clean, spacious rooms.
In the past, we have found that hotels at convention centers can create issues with noise and bad behavior. But we had no issues with that during our stay at the Courtyard, even though there was a Corvette convention taking place during our visit.
The Hilton Garden Inn is right next door and also has chargers—though only two—and could be another good choice in the area.
We found two good restaurants for our nights in Bowling Green—Hickory and Oak and Montana Grill.
We found two good restaurants for our nights in Bowling Green. The first night, we walked to the Montana Grill, which is within view of the Courtyard by Marriott. That was a well-rated restaurant, and we would rate it as good, with a very nice National Park look and feel. The second night we drove to another part of town to the Hickory and Oak, which was excellent.
Charging
Charging was uneventful for our visit to Mammoth Cave National Park—the way it should be. We left Great Smoky Mountains with a full battery thanks to the Destination Charger at Berry Springs Lodge. On the way, we stopped for lunch at Chipotle and Supercharging at Crossville, Tennessee. As always, eating our lunch took longer than the charging.
The Supercharging gave us plenty of range to drive past Bowling Green on our way to Mammoth Cave for the afternoon and then back to the Destination Charger at our hotel in the evening.
With the Destination Charger at the Courtyard by Marriott, we had plenty of range to drive back and forth to the park and to dinner in Bowling Green.
With the Destination Charger at the Courtyard by Marriott, we had plenty of range to drive back and forth to the park and to dinner in Bowling Green. And we left with a full charge for our next destination, the Gateway Arch in St. Louis, after our two-night visit in Bowling Green and Mammoth Cave.
This is the way the charging will always be in the future. Start the morning with a full “tank,” charge along the way while eating lunch, and charge again at the next destination. And this future is not far off, as most of our stops on our National Parks electric road trip are already this way, with more Destination Chargers and Superchargers being added all the time. In fact, in the year since planning this trip, there are already more options for hotels with Destination Chargers, and the relatively few gaps in the Supercharger network are being rapidly filled in.
As another option for charging at Mammoth Cave, there is also a Tesla Supercharger in Bowling Green. But with Destination Chargers at the Courtyard, we did not need to use the Supercharger. When available, Destination Chargers are always the preferred choice because they are typically free, save time by charging overnight rather than during the day, and allow a full charge when needed.
Destination Charger at Berry Springs, Great Smoky Mountains
Supercharging at Crossville, TN (34 kWh @ $0.34) $10.59
Destination Charger at Courtyard by Marriott, Bowling Green, KY
Total Supercharging for the trip $195.64
Hiking Trails and Other Activities in the Parks
We knew in advance that we would be taking two cave tours during our visit to Mammoth Cave National Park. What we did not know was how many above-ground trails surround the area of the Visitor Center—and how interesting they would be in helping to understand the geology of the cave system. If you visit, make sure you allow time for seeing at least some of those trails.
If you visit, make sure you allow time for seeing at least some of the above-ground trails.
The other surprise about Mammoth Cave is how much surface area the park covers. You get an appreciation for that as you drive several miles from the park entrance to the Visitor Center where the cave tours originate. It’s not just about the cave tours below ground. There are large areas above ground to explore within the park and lots of nature trails and camping sites.
River Styx Spring, Echo River Springs, Sinkhole,
and Heritage Trails 3.7 miles
Domes and Dripstones Tour .8 mile
Extended Historical Tour 2.5 miles
Total Hiking Miles for the trip 60.7 miles
Impressions
Mammoth Cave is well named. Until you have walked through miles of underground tunnels, it is difficult to appreciate the cave’s vastness. The local Rangers have it right when they call it “the Grand Canyon without a roof.” Like the Grand Canyon, the park is well worth a visit, both to appreciate its enormity and to gain an understanding of how powerful geological forces have changed and shaped the Earth over millions of years.
If your time is limited, you can’t go wrong with the Historic Tour, or its Extended version. But two different tours are definitely worth the time and expense to gain an appreciation for both the size and diversity of the cave.
Visit Duration: The duration of a visit to Mammoth Cave is pretty straightforward—a day to do a tour or two, with a little hiking around the Visitor Center to get an understanding of the geology of the area. We did our above-ground exploration during the afternoon of our arrival, and that was enjoyable. But there is enough time between two tours—one in the morning and one in the afternoon—to eat lunch and do some hiking around the Visitor Center in one day.
Camping in the area is also an option, which could extend a visit to a couple of days, if desired.
On the morning of April 29, we left Bowling Green and Mammoth Cave, heading north and west through Kentucky and Indiana—and very briefly, Illinois—for our next national park, the Gateway Arch in St. Louis, Missouri.