Less popular than the rural regions of the far northwest, the mountainous area north of Hanoi is attractive because of its paucity of other travelers -- though this also means a matching paucity of decent hotels, restaurants, and services. Roads are rough and prone to landslide, and many are under construction. It's best to hit this loop on a Minsk motorbike (for the adventurous only) or a jeep. To start the most popular route, go north from Hanoi, past the airport, and to the rather uninteresting burg of Thai Nguyen; then follow Route 3 farther north to Bac Can (168km/104 miles north of Hanoi) and onto a small side road that takes you to Ba Be National Park, a cache of protected land around a large lake and inland waterway. Ba Be, and the nearby town of Cho Ra, are both good places to stay overnight. From there, explore the park, and then return to the main road north and head to Cao Bang, a riverside provincial center that is a good base for exploration to surrounding hilltribe villages. Outside of Cao Bang, you can visit the caves where Ho Chi Minh holed up after returning from China, as well as one of the region's most stunning waterfalls, Ban Gioc. From Cao Bang, return directly to Hanoi, or set out east to the unremarkable city of Lang Son, a journey that is "about the journey, not the destination." The ride itself, dotted with ethnic hilltribe villages, is what's worth seeing, not provincial Lang Son. The road between Lang Son and Hanoi is a superhighway and a good choice back to the capital (there is also train service).