This tunnel is carved into the side of a mountain and is known as the "Gateway to the Red River gorge."

900 Feet Long and Only One Lane: Nada Tunnel

When driving up to this tunnel you'll notice it blends in seamlessly with the scenery since it's carved into the side of the mountain.  However, you'll want to proceed with caution, as this long tunnel is only big enough for one vehicle to pass through at a time.

Recently Hidden Gems Travel USA shared an interesting post all about Nada Tunnel.  The tunnel was built in the early 1900s for a local lumber company, as Nada was a popular logging town at the time.

Originally 12 feet high, the tunnel was expanded by a foot after a train load of logs got stuck and the tunnel had to be blasted to free it, creating an extra foot of space along the roof. This remarkable piece of history once facilitated timber transportation but now serves as an enchanting entry to the stunning Red River Gorge, showcasing the determination and labor of the early 20th century. If you’re in the area, add it to your list of interesting places to see! (Hidden Gems Travel)

The tunnel is only one lane, so caution will need to be used when entering the tunnel, but what awaits you on the other side is the Red River Gorge.  This is also why the tunnel has the nickname the "Gateway to the Red River Gorge."

Eerie Legends Surround Nada Tunnel

Of course with a tunnel that's only one lane wide and admittedly a little unnerving to drive through, there have been many legends surrounding the tunnel itself.  Some believe that Nada Tunnel is even haunted. Some local legends even claim that at night you'll see a glowing green light inside of the tunnel.

 Dangerous Roads named the Nada Tunnel, one of the "most haunted tunnels on Earth" and had this to say about the old tunnel:

This historic tunnel is located along Kentucky Route 77 (also known as Nada Tunnel Road). The unlit tunnel seems designed to intimidate drivers. It’s reportedly haunted by a climber who fell to his death in this area. Other sources claim is a former tunnel construction worker who died when a stick of dynamite exploded. Both of these stories are attributed to the legend that sometimes at night, a glowing green light is often seen in the tunnel.

So is Nada Tunnel haunted?  I guess you'll just have to take a road trip and see for yourself!