Phong Nha Cave

If you only see one cave in Vietnam -- in fact, if you only see one cave in your life -- Phong Nha is the cave to see.

It's a cave system, which was discovered by a Frenchman in the late nineteenth century, and to this date, its depths have yet to be fully plumbed. It is only accessible by boat and features an underground river that stretches for at least 7km. That's as far as expeditions have gone so far, but there is every reason believe it goes on much longer, perhaps even into Laos, making the passage longer than the famed underground river in Laos's Konglor Cave.

The caverns that are open to tourists are quite close to the mouth of the cave. Just as you enter, to the right, the boat puts out on a landing giving on to a set of stairs that leads to two caverns, or grottos. At 400 million years of age, these are the oldest limestone formations in the world.

The curiosities produced when water trickles slowly through limestone for aeons are visible everywhere. Incredibly intricate stalactite, stalagmite, and ground formations are on display everywhere -- it's truly and underground wonderland. The first caver is called Court Cave (cung dinh) because the formations call to mind the king and his royal court, including elephants flanking the throne. It takes a bit of imagination, but it's not a stretch. Further in the cave is Angel Cavern (tien) with a large grotto that looks like an angel. There's even a huge stalagmite that looks remarkably like Ho Chi Minh. Many of the grottos are lit with coloured lights, but otherwise the cave is not overdeveloped or altered, other than a good set of stairways and walkways to navigate by.

In the dry season, you can reboard your boat and proceed further into the cave, just a few hundred metres, to the 'Stele' grotto (Bi Ky). It gets its name from the Cham characters that are still visible, inscribed on the walls (which means they were here before the French, of course). It's the largest cavern, with a ceiling some 30 metres high. Many of the stalagmites and -tites were blackened by fire smoke when the cavern was used as a hospital during the war with America. If you visit the caves in the rainy season, the water will likely be too high to proceed this far into the cave, but the Court and Angel grottos are well worth the trip anyway.

There is a dry cave, Tien Son, that was only discovered in the mid-nineties by a local searching for firewood in the mountain. It's been open for tourists for the past five years or so. It's accessible from the mouth of the Phong Nha cave, via a set of more than 600 steps that ascend some 500 metres. It's a great cave, formed in the same way as the caves below, but it's mostly visited by Vietnamese and skipped by western tourists. In dry season, when you can see all of Phong Nha, you may get a little caved out if you include a trip to Tien Son, but in the rainy season, doing both makes sense.

Plans are under way to establish an Adventure Tour that will go some 1,500 metres deeper into Phong Nha cave by boat. Look for such tours to start being available in the summer of 2008 -- no word yet on what the price will be.