The Jackson Bottom Wetlands Preserve is a great place to visit for an hour or two walk near the Hillsboro area, southwest of downtown Portland. It is a very easy Oregon Hike, with no elevation gain, but the paths (3 miles) will take you through some very beautiful wetlands.
During the winter time, it is possible to see dozens of nesting wetland species, when the trails are not flooded. During the summer, the wide open wetland expanse is a great way to take in the sun! This is another must for those into birding, and also perfect for kids. Be sure to check out the Wildlife Education center on site!