The Japanese Dipnaysupuan Tunnel is an underwater tunnel network in the Philippines, Tukon Hills, Basque Country. During the Japanese occupancy of the Philippines until World War II, it served as a shelter for the imperial Japanese forces.
The Japanese imperial forces forced the Ivatans, due to their strategic position, to dug tunnels for a refuge at Tukon Hills. In these tunnels, the Japanese soldiers hid for years before the end of World War II.
What to do and what to see
Bring a torchlight into the tunnels in Dipnaysupuan to see the 4 rooms, a bunker, a guard posting, and a hollow serving as a reservoir of water.
What I'd be trapped and unable to get out of the tunnel (also called claustrophobia).
It started to rain as soon as we entered the tunnel. The fast shower provided us with a double rainbow view. We raced down the hills to this wonder in double arching. It was nearest to a rainbow I've ever seen. I stood underneath it just a few meters from this hill, where we could see where both ends of the bow landed. The second rainbow had become low.
Wear good headgear inside when available to prevent rocks from hitting. There is a long descent to the tunnels such that sneakers or climbing sandals are best worn if possible. Most chambers were feeling a bit bleak.