Washington and Oregon are teeming with iconic film locations, pop culture references, counter-culture references and real-life destinations that inspire fantasy. And Seattle is the perfect basecamp for exploring them all. Here are the best nerdy day trips from Seattle, from a mini Marvel universe to the actual Halloweentown. 1. Vashon Island’s Fence of Doors So many iconic stories rely on the symbolism of doors to convey change, adventure or mystique. And those doors become just as iconic as the stories themselves, from a blue police call box panel to the diagonal door of a small cupboard under the stairs. One homeowner in Vashon Island is celebrating these distinct portals with…