I would say washington park, they have a geart playground with Nike donated materal for the playground, a rubberized pavement so very safe for little ones, lots of discovery toys on the playground. only draw back is the parking meters, if you ever go across the river to vancouver , ester short parks is also nice. Summer time really nice water misting area for kids
Kenton park in North Portland is pretty nice!, brand new rebuilt playground with rubber ground in case the kids fall down.
Cully park is my almost 5 year olds favorite. Great new playground and sand play area but also a paved path that's awesome for bikes/scooters and huge open area to run.
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