5 Years ago I was wandering around Busan's busy downtown area Someyeon when to my surprise I happened upon a sign for a traditional teahouse. The sign was small and the tea house on the 4th floor. Upon ascending the flights of stairs I came to the 4th floor which was essentially the roof ! On the roof was a house which was the DaJeon tea house. Da Jeon in English is Tea Field (They used the Chinese characters).
The tea house has been there for many years now and although hard to find, is quite popular with Busan's vegans in the know as it has a very delicious vegetarian menu. While quieter on the weekdays, there is a steady flow of patrons on the weekends.
Essentially, there are two ways to get there :
The more complicated way is by heading behind the Lotte Department store in Someyeon until you arrive at the intersection pictured at left. There's a Pizza Hut and further down a Tom and Tom's coffee.
Go down the street further from the Pizza Hut to the Tom and Toms and keep going down. Eventually on your left you'll come to a WaBar
They also have various herbal teas on the menu.
Now you can count yourself as another 'in the know' as it is a rather hard to find tea house tucked in on the 4th floor up above several bars.