(1) Reach Lachung By Air
Reaching Lachung through airway is the best transportation mode if saving time is your priority.
The nearest major airport to Lachen is in Bagdogra located at a distance of 200 km in West Bengal. Bagdogra Airport is well connected with major cities like Delhi, Mumbai, Bangalore, Kolkata through regular flights.
You will have to hire a taxi and reach Gangtok first. You need Inner Line Permit (ILP) to visit Lachung which you can obtain through your travel agent. So obtain your permit while you stay in Gangtok for a day and then the next day leave early morning for Lachung. It is around 135 km from Gangtok and it takes around 5-6 hours to reach there. The most convenient and the only way to reach Lachung is to first come to Gangtok and then from there drive down to Lachung.
However, Pakyong Airport is at a distance of 135 km from Lachen, is the first airport in Sikkim. However, since the airport has been recently inaugurated, it is not well connected with major cities of India but will soon have direct flights connecting the state with other parts of the country.