Lagoon Valley Park spreads across 110 acres of open grassland and oak woodland on Vacaville’s eastern edge, with a dog park that feels genuinely spacious rather than cramped. The fenced area sits near the entrance, separated from the main park’s hiking trails and picnic grounds, so you’re not navigating dogs around families eating lunch or kids on playground equipment. The terrain is mostly grass and hard-packed dirt, which drains reasonably well after rain but can get muddy during winter.

The dog park divides into two sections: a larger area for dogs over 25 pounds and a smaller enclosure for small dogs and nervous dogs. Both are fully fenced, and there’s a water station with bowls for filling yours—bring your own or plan to refill from spigots scattered throughout the park. Shade comes from scattered oaks, though it’s limited, so morning or late afternoon visits work better on hot days. The park opens at sunrise and closes at sunset year-round, with peak crowds typically on weekend mornings, especially Saturdays.

Entry is free. Parking sits in a lot right by the dog park entrance, eliminating the need to walk your dog far from the car. Beyond the dog park itself, Lagoon Valley’s main trails circle the perimeter and wind through grassland toward a seasonal lagoon—dogs on leash are welcome on park trails if you want to extend your visit. The surface changes from mowed grass to decomposed granite and dirt depending on which trail you take. Winter and spring bring the most water flow through the park, and the landscape shifts dramatically green after rain. For summer visits, aim early before the heat settles in; temperatures often exceed 95 degrees by mid-afternoon.