IDD Code:(+84) 25
Nestled amid a nest of karst peaks, Lang Son is the capital of mountainous tang Son province. The town of Lang Son is in an area populated largely by Tho, Nung, Man and Dzao Montagnards. You'll see that many of these people continue living their traditional way of life.

Lang Son was partially destroyed in February 1979 by invading Chinese forces (see the boxed text, opposite); the ruins of the town and the devastated frontier village of Dong Dang were frequently shown to foreign journalists as evidence of Chinese aggression Although the border is still heavily fortified, both towns have been rebuilt and Sino-Vietnamese trade is in full swing again. Close to Lang Son, there are a couple of impressive caves in the surrounding limestone hills, and remnants of the ruined 16th-century Mac dynasty Citadel. Most travellers come to Lang Son when crossing between Vietnam and China: the border is actually just outside Dong Dang, a village 18km to the north. It's not a town to linger in, but if you find yourself with a few hours to spare there's enough to explore.

Information: internet access is pretty straightforward in Lang Son these days and almost every street has a little gaming place, including Đ Thanh Tam. You can expect to pay about 3000d an hour. Check out Incombank (51Đ Le Loi) for all your currency needs, and you can use up the last of your Vietnamese stamps at the main post office (Đ Ie Loi).

Sight&Activities:There are two large and beautiful caves (6am-6pm) just a few kilometres from the centre of Lang Son. In fact it's fair to say that they are now in the suburbs. Both are illuminated, which makes for easy exploration, and have Buddhist altars inside. Tam Thanh Cave is vast and seductive. There's an internal pool and a viewing point or natural 'window' offering a sweeping view of the surrounding rice fields. Just a few hundred metres up a stone staircase are the ruins of the Mac Dynasty Citadel. It's a lovely, deserted spot, with stunning views across the countryside. The Ngoc Tuyen River flows through Nhi Thanh Cave, 700m beyond Tam Thanh. The cave entrance has a series of carved poems written by the cave's discoverer a soldier called Ngo Thi San, in the 18th century. There's also a carved stone plaque commemorating an early French resident of Lang Son, complete with his silhouette in European clothing.

Sleeping & Eating:
Hoang Nguyen Hotel (tell: 870 349; 84 Pho 1 ran Dang Ninh; Ignore the unlikely mobile phone shop in the lobby, as the family that runs this place is extremely hospitable. Rooms include hot-water showers and TV, although 'satellite' is stretching it.
Hoang Son Hai Hotel (tell: 710 479; 57 D Thanh Tam; This tall and thin hotel has some of the smartest rooms in town. There is not a great deal of English spoken, but the universal language of comfort is apparent. There is even a lift, a rarity in these parts.
New Dynasty Restaurant (Phai Loan lake) By night there is only one place to be in town: the New Dynasty. Set on the shores of the lake, this vast place has a garden restaurant to the right, complete with an extensive Vietnamese menu and a draft beer emporium. To the left is a bar and beer garden with local music. It's heaving. There are plenty of other hotels and guesthouses in town, of much the same standard. Few have restaurants, but there are some com pho places in town and a couple of cheap restaurants near the bus station.

Getting There & Away: Buses heading to Hanoi's Long Bien bus station (50,000d, three hours) depart regularly from the long-distance bus station (Đ Le loi). A daily bus leaves Lang Son for Cao Bang, but it's a rollercoaster ride. Minibuses heading to Cao Bang via That Khe and Dong Khe leave regularly from the minibus station (Pho Tran Dang Ninh). Three daily trains run between Lang Son and Hanoi.

Getting Around: There are plenty of xe om (motorbike taxis) around the post office and the market. Taxi Tamdia (tel: 818181) is a reliable company for metered taxis. On Pho Tran Dang Ninh there are plenty of minibuses looking for passengers who are heading to the border at Dong Dang.

BORDER CROSSING: YOUYJ GUAN/HUU NGHI QUAN
The Friendship Gate at Dong Dang/Pingxiang is the most popular border crossing in the far north. There is nothing in Dong Dang to hold the traveller's interest, except its position as a border town. The border post itself is at Huu Nghi Quan (Friendship Gate), 3km north of town;a xe om (motorbike taxi) ride. The border is open from 7am to 5pm daily, and there's a 500m walk between the Vietnamese and Chinese frontiers.

Entering Vietnam this way, watch out for border touts herding unsuspecting travellers on to overpriced minibuses to Hanoi. 

The cheapest way to get to the Dong Dang border is to take d minibus - They cruise the streets of Lang Son looking for passengers and leave throughout the day. The fastest way to cover the 18km between Dong Dang and Lang Son is to hire a motorbike. Just make sure the driver takes you to Huu Nghi Quan, as there are other checkpoints for locals only.

On the Chinese side, it's a 20-minute drive from the border to Pingxiang by bus or shared taxi Pingxiang is connected by train and bus to Nanning, the capital of China's Guangxi province.

Trains from Hanoi to Beijing via the Friendship Gate depart the capital on Tuesday and Friday at 6.30pm. a 48-hour journey that involves a three-hour stop for border formalities. You cannot board this international train in Lang Son or Dong Dang. Check the schedule in Hanoi, as it may change. There's a train from Hanoi to Dong Dang , via Lang Son, three times a day, if you want to make your own way across the border and get on a Chinese train when you reach the other side.