If you have a spiritual bent of mind then the best thing would be to visit the famous Pashupatinath Temple. This temple id dedicated to Lord Shiva and has attracted millions of Hindu followers. Most of the people visit this temples when they are living the final days before they meet death.
The river Bagmati which flows along is considered to be the most sacred river for cremation. It is also believed that people who die here are reborn as humans again irrespective of their conduct on earth.
Highlights: You can also visit Panch Deval which has five temple complex which was a holy shrine but not place for old people to stay.
Location: Pashupatinath road , Kathamandu.
Prices: USD 29.
Best time to visit: You can viit this temple during anytime of the year but avoid visiting it during Mahashivratri and Teej festivals