Bhutan followed a policy of self-imposed isolation and was largely cut off from the rest of the world for centuries because of its most rugged and mountainous topography, as most of the country includes part of the Himalayan ranges. Until the early sixties, this landlocked tiny nation was accessible only by foot through the high passes of Tibet and the plains of India. Now, there are two ways via which a tourist can make entry and exit from Bhutan i.e. by air and overland travel.
Today Drukair, the Royal Bhutan Airlines introduced in 1983 and the recent privately- owned Bhutan Airlines managed by Tashi Air Pvt. Ltd. operate and connect Bhutan from Paro valley to various cities in South and Southeast Asia. Although Bhutan Airlines covers limited destinations of Bangkok and Kathmandu, Drukair operates to and from Dhaka in Bangladesh, Indian cities of Kolkata, New Delhi, Gaya, Bagdogra and Guwahati, Kathmandu in Nepal, Bangkok in Thailand and Singapore. Drukair also operates domestic air services providing passengers with the choice of multiple entries and exits from various parts of India. Airfares are payable in US dollars and tickets will be arranged by local tour operator such as Bhutan Engyum Travels.
The border towns of Phuentsholing in the southwest, Gelephu in the south and Samdrup Jongkhar in the southeast serve as overland entry and exit points for the tourists. However, please note that all overland travel requires an Indian visa. The overland entry and exit is convenient for tourists interested in combining their trips to Bhutan along with the North-Eastern Indian States including Sikkim and hilly districts of Darjeeling and Kalimpong in West Bengal.