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During the Vietnam War, Cat Ba Island was used as a kind of safe haven for the North Vietnamese army. Due to the heavy American bombing, a secret bomb proof hospital and safe house for the VC leaders was built inside a cave, high up on one of the many limestone karsts which dominate the island. The hospital could not be seen from the ground or the air, making it the perfect spot for a safe house.

It was abandoned after 1975, but now it is a popular tourist attraction on the island.

As I climbed up the steps which lead up the mountain, I would never have even known that there was a cave here, and even when I got close to the cave mouth it wasn’t easy to see that there was any habitation inside.

View from the Hospital Cave entrance on Cat Ba Island, Vietnam

View from from the entrance to the cave

Entrance to the hospital cave on Cat Ba Island, Vietnam

Entrance to the hospital

This secret hospital was actually built into three different levels. The first level is entirely man made from concrete, and after entering through the tiny door, it was quite eerie inside even after our guide turned on the lights. We were the only people there.

Hallway inside the hospital cave on Cat Ba Island, Vietnam

The hallway on the first level

The rooms are all empty, but our guide told us about what each room was used for, most of which were hospital rooms for injured soldiers as well as surgical rooms and doctors offices.

Empty room inside the hospital cave on Cat Ba Island, Vietnam

One of the first level rooms in the hospital

The second level of the hospital is much smaller and its walls are mostly natural rock. Up here there was a swimming pool and the natural cavern was used as a cinema.

The tiny third level had offices for the VC leaders who used the facility as a safe house.

Natural cavern inside the hospital cave on Cat Ba Island, Vietnam

The cavern on the second level, which leads up to the third level. This cavern was used as a cinema.

Swimming pool inside the hospital cave on Cat Ba Island, Vietnam

The swimming pool

The hospital is a true feat of engineering, with ventilation shafts and fresh water access. They even had a quick escape route from the upper levels straight to the bottom level, as well as a second entrance for a quick escape if the cave was ever invaded.

Second entrance to the hospital cave on Cat Ba Island, Vietnam

The second entrance to the hospital cave

The guide who showed us around the cave was excellent and knew everything there was to know about this secret hospital. Definitely check it out if you head to Cat Ba Island.