First time visitor!

One experience that is a must for every newcomer to Zihuatanejo is the morning fish market at the docks next to the Cancha (basketball court and public venue space). The fishermen leave the previous evening and bring back their wares to sell early morning. If you aren't an early riser, buck up one morning and make your way downtown between 6 and 8 am. You can't possibly get fish any fresher unless you catch it yourself.

Excellent recommendation! The amount of activity at dawn when the fishing boats arrive is AMAZING.