The national park outside Hue is among the best in Vietnam, and spending a night or two here is highly recommended. The protected area stretches right across the country sideways, from the South China Sea to the western border with Laos. The 1450m summit of Bach Ma was used as a helicopter landing base by the American army during the war in Vietnam, and the area was heavily defoliated during the fighting, but has had about forty years to bounce back, and while the growth isn't quite as lush as it might have been otherwise, it's still uniformly green.
There are two types of forest here -- sub-tropical evergreen monsoon forest above 900m, and tropical evergreen monsoon forest below that mark. It's known for its beautiful waterfalls, hiking trails, and decaying French villas which dot the landscape. It's also known for its wide variety of native wildlife, including rarities such as the Douc Langur, Asiatic Black Bear, Leopard and Stump-tailed Macacques, as well as wild pigs and deer. A lot of these critters are more active at night, so it takes some patience and persistence to spot them during the day. There's excellent bird-watching here as well, but of course, to get a peek at them, you'll have to get up at the crack of dawn. There are about 65,000 tribal inhabitants within the national park 'buffer zone,' including a settlement called the Khe Su hamlet, which can be visited while you're in the park.
It's a 14km hike to the summit, which has gorgeous views in clear weather that reach all the way out to the China Sea. Clear weather, though, can be a bit of problem -- as this is one of the rainiest spots in Vietnam, and also one of the coldest all year round.
For those who want to skip the 14km hike, jeep taxis are available for groups of up to 4,the trip takes 45 minutes. You can also bring your own transport, but motorcycles and bicycles are not permitted to attempt the ascent.The park currently does not have tents to rent-out, though you can camp if you bring your own.