San Diego County Fair 2025 Theme Exhibit. With the 2025 san diego county fair approaching with a “let’s go retro” theme, the del mar fairgrounds board has approved the themes for the following two. With a nod to nostalgia and a focus on fun, the 2025 fair will give our yesteryears another moment in the san diego sun.

The convention, which draws over. Fairgrounds officials have already set the theme and dates for next year’s san diego county fair, inspired by the outdoors.