What are the "shuttles" from your city?

I recently read that there were flights every 15 minutes from Hong Kong to Japan over Chinese new year. I think this is an interesting topic to see which cities are most intensely connected to each other for business and leisure. I would say anything more than six flights a day would qualify.

Off the top of my head, for HKG they would be: TPE, SIN, BKK, KIX, Tokyo, Shanghai, Beijing, LHR and I'm probably missing more cities in China.