Walnut Creek Model Railroad Society

Two playgrounds (tot and big-kid) plus Walnut Creek's gated spray ground with a small water slide and lifeguard - wet and dry play in one stop. Lindsay Wildlife Experience and the model railroad are on the same grounds, so a playground morning easily becomes a full day.

Wildlife museum with daily animal meet-and-greets and hands-on activities.

The full-service downtown-adjacent Marriott with an outdoor pool and easy walks to Broadway Plaza - a solid base for a Walnut Creek weekend with kids.

The toddler-and-preschool playground of Walnut Creek: small, modest structures close together so one parent can see everything, shaded benches under three big oaks, and paved loops where little kids lap on trikes and scooters.

All-suite layout (parents get a door between them and the kids), free cooked-to-order breakfast, an evening reception, and an indoor pool that works in any weather - the family-math champion of Walnut Creek.

The Contra Costa splurge stay: hotel guests get access to the attached Bay Club's pools, tennis, and kids' club programming - the closest thing the county has to a resort for families.