You need not worry too much about how to reach Gangtok. You can take a flight or train if you want. But we recommend that you drive to the place if you are from the vicinity, or hire a taxi.
By Air: The nearest airport to Gangtok is Bagdogra in West Bengal. It is almost 124 kilometers away from the destination. You can hire a cab or a shared taxi from the airport and reach the tourist destination in 2 hours. Depending on the weather condition, helicopter service is available from the Bagdogra airport to Gangtok.
By Rail: The New Jalpaiguri station in Siliguri is the nearest railway station to Gangtok. Taxi services are available from the station to the destination which is 148 kilometers away. You can reach the spot in 3 to 4 hours.
By Road: There are public transport vehicles from nearby cities to Gangtok. A shared taxi is very common in these areas. If you prefer to drive yourself, you will have a wonderful time. You can reach Gangtok from Siliguri, Darjeeling, Kalimpong, and Kolkata. The roads are mostly in good condition. So you need not worry about that.