4+ days from Varanasi to Bodhgaya (by train) and back.
Varanasi and Sarnath
7+ days From New Delhi (by train) to Varanasi and back
Darjeeling and Sikkim
3 weeks The Big tour to Darjeeling and Sikkim, from the Bagdogra Airport via Darjeeling, Pelling, Yuksom, Tashiding, Gangtok.
Ladakh and Zanskar
3+ weeks The famous Indian NH1 road, via Jammu, Srinagar (an overland or a motorcycle tour).
Shigatse, Lhasa, Gyatse
10+ days from Kathmandu (Nepal) via Yamdrok Tso.