This, according to ICIMOD, is a wiggly line which might form a possible route of the GHT – the Great Himalayan Trail. Basically it is a long distance trail with out a route. You need a pile of good maps and a local guide and then you can choose yourself where you walk!
Previously it (one route) has been walked in 68 days by Rosie Swales. Will be interesting to hear of other people walking the length of Nepal.