I’ve hiked many sections of the Himalaya, but never out of West Bengal.
The route of this trek lies along the border of India and Nepal. In fact, one constantly moves in and out of Nepal during the trek. The mighty mountains, of course, know no boundaries. They stretch through Nepal, India, Bhutan and further.
This trek can be done almost throughout the year save for monsoon months. …
Click PLAY or watch it on YouTube.
Guided it costs only about 10,000 Indian Rupees (less than $150) for 6 days.
besthike.com 
Very interesting article.