Rare Tunnel Crossing for People Who 'Walk Under Water'

Kitakyushuー The spacious elevator opens, and a group of cyclists with their chic road bikes emerges. In their 40s, the Japanese men are looking slightly worried. They are searching for something: the toll box. It will cost them ￥20 JPY (13 cents US) each to cross the Kanmon Pedestrian Tunnel that connects Japan's main islands of Honshu and Kyushu. But the toll box is nowhere to be found.

*Elevator entrance to the pedestrian tunnel from the Kitakyushu side. (©Agnes Tandler)*

Did they miss it on their way into the elevator? There is certainly nobody waiting to collect the fee here, 55 meters below the surface. Actually, there is nobody to ask for help, either. "Let's go back up to check," one of the men suggests. Confused, the group steps back into the elevator to look for the toll box at the entrance on the Shimonoseki side of the tunnel.

Thankfully, pedestrians can walk through the tunnel for free. They do not have to worry about locating the unattended toll box. Claustrophobes, however, should better stay away from the Kanmon Pedestrian Tunnel altogether. The walkway runs 60 meters under the ocean. And as you move away from the surface of the earth at its entry points, at times it can feel a bit restricting, to say the least.

However, it takes only about 15 to 20 minutes from one end of the tunnel to the other. Visitors enter the tunnel via elevators at Moji-ku in Kitakyushu City, Kyushu, or at Shimonoseki City on the Honshu side.

*The pedestrian tunnel inside can look eerie. (©Agnes Tandler)*

Prefectural Underwater Border Crossing

Inside, the tunnel is narrow, with a passage only four meters wide. Given its impressive length of 780 meters, there is no way to see the exit point, let alone the proverbial light at the end of the tunnel. There is also the brown clay pavement and the seeping salt water that forms little puddles inside the tunnel. At times, these can make the crossing feel like a leap of faith.

The Kanmon Pedestrian Tunnel connects Japan's main islands of Honshu and Kyushu. At the same time, it also links the two prefectures, Fukuoka in Kyushu and Yamaguchi on Honshu. In fact, that prefectural border runs right through the middle of the Kanmon Strait.

*A line marks the prefectural border between Fukuoka (upper side) and Yamaguchi. (©Agnes Tandler)*

The border is clearly marked by a thick line drawn on the pavement in the tunnel. It makes for a good photo opportunity ー or just hopping back and forth between Yamaguchi and Fukuoka for a bit. Since the tunnel doesn't get too many visitors, it is perfectly fine to take a moment to enjoy the rare experience of an undersea border crossing on foot.

*Sign inside the tunnel marking the distance. (©Agnes Tandler)*

Nowadays, there are certainly more popular and faster ways to cross from Honshu to Kyushu or vice versa, but few that are this unique.

Two Stories, but No Cats and Dogs

Most underwater tunnels are designed for cars or trains. A tunnel that allows people to cross a water body on foot is pretty unique. Only a few exist in the world, and these mainly run under rivers in Germany and England.

Construction for the Kanmon undersea tunnel began in the 1930s. It was paused during World War II and only resumed in the 1950s. Eventually, the tunnel finally opened in 1958.

Another unique feature: The tunnel has two stories. Its upper level serves cars and trucks, while the lower section is exclusively for pedestrian use.

Cyclists and low-power mopeds are permitted to pass through the pedestrian part as well. However, they have to dismount and push their vehicles through the tunnel. Dogs and cats, meanwhile, are strictly banned, so taking your dog for an underwater evening walk is not an option.

*Sketch showing the layout of the tunnel. (©Agnes Tandler)*

The tunnel's smooth pavement makes it popular with runners, particularly at night, when it is raining, or on a hot and sunny day. Deep inside the tunnel, joggers find protection from the elements and also excellent visibility.

It is open from 6 AM to 10 PM daily. That gives everyone plenty of time to walk or run back and forth between the islands of Honshu and Kyushu.