The Langtang region is less well known than the more famous Everest and Annapurna regions but it offers some of the best short trekking routes in Nepal. Its the fastest way to get up into high altitude scenery, in addition there are many lower altitude trekking routes between the villages in the area. I have not explored this region as thoroughly as the other two regions having only hiked the Langtang Valley on two occasions, each just a short trek up the valley. There is the possibility to link the area with Helambu, Gosainkunda, and the Tamang Heritage Trail for longer treks. The route up into the Langtang valley is relatively short and crosses no high passes. It is possible to go from Kathmandu up to 4000 m high altitude scenery in as little as two and a half days. Although if you are not previously acclimatized it would be wise to take it slower than that. Using Kyangjin Gompa as a base it is possible to do numerous day hikes throughout the valley reaching altitudes in excess of 5000 m. If you have a tent and a bit of food your options are even greater. I would rate this as the best short trek in Nepal. Find a local guide for the Langtang Trek
There have been several solo trekkers who have gone missing and were likely murdered in the Langtang region. Though it is unlikely anything would happen its probably best to trek with others even more so in this area, especially for women.
Do It Yourself Information
Nice day hikes include the 5000 m hill behind Kyangjin Gompa, also cross the bridge south of Kyangjin and take the path that heads up to the Gangja La pass. Unfortunately the pass was snow bound when I was there but you can loop around and decend down a ridge further up the valley. It is a beautiful hike through forests meadows and with great views across the valley at 7227 m Langtang Lirung. You can also hike up to the upper Langtang Valley and the Langtang Glacier. Opportunities for exploration are almost endless. I returned to the Langtang region in spring 2010. As of fall 2009 apparently many of the locations along the trail at the cohesion of the large lodge owners had formed "committees" to standardize room rates and food. While before there had been standardized menus but you could often work out deals for free rooms and discounted food with smaller lodges. Now it seems with threats of physical violence as well as property damage by the "committees" against lodge owners who break this seems no longer possible for rooms. It seems to have hurt the small lodges who can not compete when all prices are equal. Only four of the 22 lodges in Langtang village were open in April a high tourist season forcing all the tourists in to a few lodges. Fortunately I managed to secure a homestay with a family in the old village a much better experience. You can try striking up conversations with villagers to explore these opportunities. I talked with other individual trekkers who complained they got stuck in one of the few open lodges with big organized trekking groups and were therefore low priority for the lodge. I would say the best option is to stay at places in between the main places. Avoid Lama Hotel (the traditional first night stop) where the lodges charge an outrageous 400 rupees for a double, considering Kyangjin Gompa was only charging 300 and Lama Hotel is less than a days walk from the road. Riverside an hour after Lama Hotel, or Rimpoche before are good alternative places to stay. Also I would either avoid Langtang village or talk your way into a homestay it was very depressing there this time around with so many closed lodges. Kyangin you really have no choice but to stay there, and the surrounding area is beautiful. Its still a very nice hike but the "committee" thing has ruined some places, we'll see how long they can keep up the enforcement.