No. Quote from their website: "The Tualatin Hills Nature Park is a wildlife preserve, so we ask that you please leave your dogs and other pets at home when you come to visit." http://www.thprd.org/parks-and-trails/detail/tualatin-hills-nature-park
No it is not simply focused on the building. The signage there specifically says that dogs are not allowed into the park as to not scare and disrupt the wildlife.
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