A few days will not help you to explore the vibrant city of Kathmandu but if you do not have too much time remember that you cannot miss:
– Flight over Everest
No trip to Nepal is complete without a mountain flight. You must get up early to do it and do not take into account that it is not too cheap an activity. The planes that make this flight are 21 seats so it is better that you book and do not show up without anything. You may be allowed to pass in the cockpit to get a better view of the most impressive panoramic views. The price of the flight hour is $ 175. 
– Bhaktapur Durbar Square
It is one of the three main squares of the Kathmandu Valley Palace. Surrounded by traditional architecture, the square is not only a tourist center, but a meeting place for the local inhabitants. It is also the home of the goddess Kumari. The square also features the Golden Gate, the 55-window palace, and a statue of King Bhupatindra Malla. Another square that you should not forget is Patan Durbar. 
– Boudhanath Stupa
You may be close to the center of Kathmandu, but life at the Boudhanath Stupa works at a more leisurely pace. This is the nerve center of the Buddhists of Nepal. You will see many monks who live peacefully and who kindly welcome tourists. The surrounding shops sell a wide variety of traditional Tibetan jewelry, as well as local handmade pieces, clothing and souvenirs. Gifts are generally more expensive than in Thamel’s main shopping district, so you’ll have to haggle.