It can be nice to purchase a watch from the city where it was made. Your warranty card will say "Bienne" on it, and the person selling it to you typically knows the brand very well. Here are the local branded boutiques and authorized retailers for the main Bienne brands.
Note: Rolex had an AD in Bienne until January 2022. That is no longer the case but I will continue to monitor the situation and update this section accordingly.
Vintage & Second Hand
You can make some great finds in Bienne, but to avoid disappointment, it's worth being cautious of open hours, as most places below only open a few days a week, and/or during half a day. There are several other places to choose from, the ones mentioned here are my personal "go-to" destinations.