Before departing Cao Bang, consider climbing the hill up to the War Memorial for a great panoramic view. The famous Highway 4 winds its way through steep mountain passes with spectacular vistas! Lang Son, the capital of this mountainous area, is an important crossing and trading route with China. The area is home to Dzao, Man, Tho and Nung ethnic minority groups. Lang Son has two markets, the Old Market and the Dong Kinh Market, where shoppers can find everything from electronics and gadgets to textiles and house wares. Just a couple of kilometers from town are two large, beautiful caves and the ruins of the Mac Dynasty Citadel that are worth a visit, time permitting. Tam Thanh Cave contains a pond and offers great views of the surrounding farmlands. Nhi Thanh Cave, formed by the river that flows through it, has poems carved into the entrance by the man who discovered the cave in the 18th century. The late afternoon trip back to Hanoi from Lang Son is along a modern 4-lane divided highway. Trip ends around 8pm.