Parts of the Far North are particularly isolated and difficult to visit. However, this isolation adds to the region's beauty, as many areas are still extremely unspoiled, and distant from the popular tourist trail to reach Ba Be lakes in Bac Can province is a challenge, but one well worth pursuing. The road between That Khe and Lang Son, whose beauty of plunging ravines riddled with caves, hides a grim and bloody past, is also worth the effort to see. To the North of Cao Bang is Pac Bo, near the cave in which Ho chi Minh lived upon first returning to Vietnam from China. The Far North of Vietnam is home to numerous tribes of ethnic minority groups. They live in some of the most isolated places, subsisting through traditional means. Some of the tribes you may encounter are the Tay, Nung, Zao, H'mong, and the San Chi. Farther afield in Ha Giang province there is a variety of hill tribes numbering from several thousand members to only a few hundred people.
This guide follows a path beginning in Thai Nguyen, to the North of Hanoi, and heading North to Bac Can and the Ba Be lakes before moving Northwest to Cao Bang. From there we head South through Dong Khe and That Khe to Lang Son, the other main gateway between China and Vietnam for foreign visitors.
The only reason you would want to stay in Thai Nguyen was if there was a flood and all the roads were impassable. For those that want to explore Thai Nguyen, it just has the remains of a citadel from the early 1800s, and a Museum with exhibits of the ethnic groups in the Northern region. Thai Nguyen is also an important player in Vietnam's steel industry.
Ba Be Lakes in Bac Kan province
The road from Thai Nguyen to Bac Kan is in pretty good condition and passes through some very scenic areas, esp. the bowl-shaped tea hills . Among all the regions planting green tea for domestic use and export in Vietnam, Thai Nguyen offers the best and sometime you may mistake that the Vietnamese is keen on foreign products if they mention about the excellent "Thai tea".
The only real sight in Bac Kan is Ba Be Lakes, 230km from Hanoi and 80km to the Northwest of Bac Kan town. "Ba Be" means "three seas", an ornate expression which just means the three big lakes. It's several kilometer from Ba Be Guesthouse to the Main Wharf, from which you can rent a boat and turn right to row or run along the Nang River. The river trip is a marvel: there are a clear flow and a muddy flow, which (incredibly) do not mix, on the same riverbed (!); and you can either jump in the clear water for a swim or simply lye on the boat contemplating the wonderful untouched nature surrounding with bamboo clusters, lianes and flowers along the riversides and watching the fishermen in their piraguas fishing aquatic products. After 3km you will reach Puong Cave, a mysterious sight with twilightful stalagtites and stalagmites, which seems like the end of the river. But if you meander by boat some 300m inside, the river will be finally opened and you escape from the cave. It takes you an hour more to reach Dau Dang Waterfall that is quite sightworthy. Reaching the lakes is going upstream from Dau Dang, turning right to a small flow, then going ahead 1km more. The Lake Zone, 8km long and 3km wide, set in a picturesque national park and contain 3 lakes surrounded by vertical rock walls, from which many currents fall down between many kinds of creepers cling, and a wild forest where many species of birds abound. If you have time, you can also have another visit to a village-on-stilt by taking a boat from the Main Wharf and turn left, go for 4km till you reach the small village's watering place and get some experience of a working day of the farmer and fishermen over here.