You can go for overland travel to enter Nepal from both India and Tibet. If you are in Tibet, you can enter Nepal by crossing the border at Kodari. Thereafter, take a bus to Katmandu. This will take you 7 to 12 hours depending on the road conditions.
The easiest and hassle free overland route to Nepal from India is via Gorakhpur using train and the Sunauli/Belahiya border post. The only direct buses from this route to Katmandu run at night and take approximately 9 hours. Raxaul/Birgung border post can also be used to visit Nepal. But this may not leave you with a pleasant traveling experience. If you are in Darjeeling you can come to Nepal via Karkabhitta. There are also several border crossings in west Nepal.
Katmandu is the only international airport in Nepal. There are a number of International Airlines with direct flights to Katmandu.
Thai Airways International operates daily flight between Bangkok and Katmandu. Qatar Airways flies daily between Doha and Katmandu with connecting flights to/from Europe and America.
Gulf Air has daily flight between UAE and Katmandu with connecting flights to/from Europe and America.
Air China flies between Lhasa, with connecting flights to/from mainland China.
Austrian Airlines flies between Vienna and Katmandu once a week Indian Airlines have frequent flights between Delhi, Calcutta and Katmandu.
Nepal Airlines fly - between Hong Kong and Katmandu. Between Bangkok and Katmandu. Between Singapore and Katmandu via Bangkok. Between Osaka and Katmandu via Shanghai. Between Delhi and Kathmandu. Between Bombay and Katmandu. Beside these there are Biman Bangladesh.
Jet Airways, Pakistan Airlines, connecting Kathmandu with many countries. Visa and Entry Procedure All visitors except the Indian nationals must hold passport and valid visa. Visa can be obtained at the Nepalese diplomatic missions and consulates abroad. Visa is also issued at the entry points. It can be extended at the Department of Immigration, Bhrikutimandap, and Katmandu. Children under 10 years need not pay any visa fee. People willing to get entry Visa at the air port or any of the land entry points are required to fill a visa form with passport photograph. So, please download form from the link below an get ready while you are passing through the immigration Point.
Visa Fee –
Gratis visa for all tourists who visit Nepal for 3 days or less.
Gratis visa for tourists of SAARC countries and People's Republic of China.
Multiple entry visa- Upon arrival in the KTM airport fill out the necessary form and proceed to the visa line.
US$25.00 paying for 15 days, US$40 paying for 30 days & US$100 paying for 90 days visa. Please bring 2 passport photos (one for the visa and 1 extra).