The journey from Dharmavaram to Gangtok covers about 2300 km. You will need to take a train to New Jalpaiguri and then a taxi or bus to Gangtok. The total travel time is approximately 45 to 50 hours. Gangtok is a beautiful hill station.
Total Distance: 2300 km by road, 1900 km straight-line.
Book a shared taxi from NJP station.
March to June for pleasant weather.