Permits and transportation
In addition to an Indian visa, foreign travelers must possess an inner line permit, issued by the Indian Ministry of Home and Affair or New Sikkim House both in New Delhi, to visit Sikkim. The permitis valid for 15 days. If you are visiting the interior regions, you also require a protected area permit which is obtainable in Gangtok from the Department of Tourism. Tour arrangements should be made through a registered travel agent who will handle the official formalities. 

Transport services are provided by four-wheel drive vehicles. Taxis are available for getting around Gangtok. Sikkim Helicopter Service operators sight seeing flight to different points in Sikkim.

General information
Sikkim is a mountainous land crisscrossed by deep ravines.

Access: from Kathmandu, fly to Bhadrapur in east Nepal (1 hour), then drive to Kakarbhitta (Nepal-India border 34 km), to Siliguri (36 km) and to Gangtok (110 km 3 hours and 30 minutes), Gangtok is also connected by road with Darjeeling (5 hours) and Bhutan (7 hours)

The closest Indian airport is at Bagdogra, 124 km from Gangtok, where scheduled flights operate from Culcutta, New Delhi and Guwahati. Taxis for Gangtok (4 hours) are available at the airport. Sikkim Tourism Development Corporation also operates daily helicopter flight from Bagdora airport to Gangtok (20 minutes). The closest railway stations are Siliguri and New Jalpaiguri (121 km) which are connected to Calcutta, New Delhi, Guwahati and other major Indian cities. Taxis and buses for Gangtok are available at Siliguri.

Season
March to May and October to December are the best times to visit. Bring light woolen clothing during summer (maximum temperature 20.7 degrees Celsius) and heavy woolens during winter (minimum 7.7 degrees)

Adventure: Trekking, mountaineering, rafting and Yak safari.

Accommodation: there are modern hotel and restaurants in Gangtok. Comfortable resort lodges are available in the outlying areas.