Yoshan Tea
Being there
Go up to the first floor and ask the owner to show you how to brew an oolong. At the back you can see the tea roasting over charcoal.
The story
In 1869 a British merchant shipped two boatloads of Taiwanese oolong to New York under the name "Formosa Oolong", and it sold out. Tea houses soon lined the riverbank of Dadaocheng, and the streets filled with women sorting leaves. Most of those houses are gone. A few still roast the old way, slowly over charcoal, and the first thing you notice walking in is that smoky, toasted smell.