durbar square architecture
Most of durbar square (they have 3, kathmandu, bhaktabur and patan durbar square) is very rich in architectural details. And these durbar square is said to be built during Mala Dinasty. Most people should at least visit the kathmandu durbar square (walking distance from Thamel area), if they have more time to spend, then Bhaktapur durbar square (around 45min from Thamel) shouldn't be missed. It's bigger and older than Kathmandu durbar square, and they produce pottery lines there.