Pa Thom Cave

The cave lies in Pa Thơm commune, in Điện Biên. The Thái people there named it Thẩm Nang Lai. In the Thái language, "thẩm" means cave and "nang lai" means fairies. Together the name means "the cave of many fairies". The Thái are one of Vietnam's ethnic groups. The fairies belong to folk legend. The cave itself is a limestone karst cave. Its entrance stands 12 meters high and 17 meters wide. Nine vaulted chambers stretch on for more than 350 meters, and the stalactites show dreamlike colors that make a visitor stop and stare.

The way up to the cave is a climb of more than 200 meters through forest and boulders. It is not very long, but it asks for strength. Looking back down, the roofs of Thái stilt houses lie scattered in the valley below. The Nậm Nứa stream winds between them, and the mountains of the Northwest rise layer upon layer in the distance. Mass tourism has changed little here. There is no drink stall along the path, no restaurant near the cave, and no crowd waiting. There is only forest and rock and sky.

The Thái who live here see this view every day, and they call the cave above it the cave of many fairies. That is no accident.

At the entrance, the first surprise is its size. It is 12 meters high and 17 meters wide, as tall as a building of four floors and as wide as a street with two lanes. All of that space is the natural doorway of the cave, an arch shaped by limestone over millions of years.

On the right side of the entrance, a block of stone juts out in the shape of an elephant's head. The Thái of the area regard it as the guardian of the cave.

Stepping inside, you feel the change at once. The temperature drops sharply. Outside it can be above 30 degrees Celsius, and inside it is as cool as a natural air conditioner. The light changes too, from glaring sun to deep dark. This is where a flashlight becomes necessary.

Pa Thơm has nine vaulted chambers in a row, each with its own size and shape, and more than 350 meters in all. Groundwater, over millions of years, dissolved the limestone and carried it away bit by bit, leaving hollow space inside the mountain. Later, when water no longer flowed through, the minerals it carried began to gather, drop by drop. They formed stalactites hanging down and stalagmites rising up.

The stalactites come in many colors, depending on their minerals. White comes from calcium. Brown and yellow come from iron. Pale green comes from copper. When a flashlight beam falls on them from different angles, their colors and shapes change completely.

In 2009, the Ministry of Culture, Sports and Tourism recognized the cave as a national heritage site. But the cave has not been built up for tourists. On ordinary days it is completely dark inside, and the only light is the one a visitor carries. Electric light reaches inside only at festival times and at Tết.

That lack of change is what makes Pa Thơm precious. There are no garish colored lights like those in the big show caves, and no concrete path to hide the cave floor. There are only stalactites left whole, and the natural dark.

Pa Thơm lies about 30 kilometers west of the city of Điện Biên Phủ. No mass tours come here, and no buses. Most visitors to Điện Biên have never set foot in this place. Thẩm Nang Lai, the cave of many fairies, is still a secret of this land.