Nowadays you can go from Kyushu to Honshu by walking through the Kanmon Pedestrian Tunnel.

As you walk through the tunnel, you can tell you’re walking under the sea as you hear the sound of the waves above you.

Here’s how you use the Kanmon Tunnel: You take the elevator down in Fukuoka, walk straight for about twenty minutes, and before you know it you’re looking at a sign that tells you you’re in Yamaguchi. From there you take the elevator up to the ground floor, and just like that, you’re in a different prefecture with a completely different view.