Concierge.com's insider take:
Gas Works Park was once a belching natural gas production plant. Remnants of the site's industrial past remain (a tangle of towers, pipes, and catwalks), but the main attraction is a gigantic grassy hill, typically covered with kite-flyers and picnickers enjoying one of the city's best water views (N. Northlake Way at Meridian Ave.). Discovery Park is a local favorite in the charming neighborhood of Magnolia. At 534 acres, it is Seattle's largest preserve, with nine miles of footpaths, two miles of beach trail, great bird-watching, a lighthouse, and sweeping views of the sound (3801 W. Government Way at 36th Ave. W.; 206-386-4236). Washington Park Arboretum is home to an internationally renowned collection of trees and plants from the Pacific Northwest (N. of Madison St. on Lake Washington Blvd. E.; 206-543-8800). Volunteer Park is in the heart of Capitol Hill. This is a true neighborhood park but it's also home to the striking Seattle Asian Art Museum. In addition, there's a small conservatory, and an observation deck in an old water tower from which you can see the water and the Space Needle (1247 15th Ave E.; 206-684-4555).