Historical temple of Changunarayna is famous for archaeology of nepal. Nepal used to be 22 and 24 different stated and kathmandu valley was just Nepal, at that time Changunarayna was a fort.
Changu is famous because of its history and things that happend there then. Changu narayan is listed in one of the unesco world heritage site in kathamndu. Changu narayan temple dates back 1st century bc.