To enter the frontier of Nepal, the passport (not identity card) is required and it must be valid at least for six months.
Visa
I. Yes, One can get a visa at the Nepalese Embassy or Consulate or at the Kathmandu airport upon arrival.The visa can also be obtained from the different entry points of Nepal.
II. A visitor will have to fill up a form with one passport size photo.
Single entry: US $ 30 for 60 days.