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By Air : To Bagdogra,then by road to Sikkim via Siliguri
By Rail : To New Jalpaiguri,then by road to Sikkim via Siliguri
By Road : To Siliguri,then by road either via Kalimpong/Darjeeling,or else directly to Sikkim
Also limited helicopter services from Bagdogra to Gangtok/Pelling.