The Plaza Principal is the social center of Sayulita — a shaded square with a central gazebo, surrounded by restaurants, shops, and the kind of benches where sitting and watching the world pass is entirely acceptable as an afternoon activity. It's compact enough that you can see it all from one spot, which makes it oddly useful for getting your bearings when you first arrive.
The square is where festivals happen, where children play in the evenings, and where vendors set up before they move to the beach. On weekday mornings it's quiet; on weekend evenings it fills with a mix of tourists and locals from surrounding towns who come in for the night. The energy is relaxed without being empty.
The surrounding streets — particularly Calle Delfines and the lower end of Revolución — are where most of the shopping and evening restaurant activity concentrates. The plaza works well as a base for wandering, with the beach a two-minute walk in one direction and the market street in another.