A 20-mile ride around Seattle’s clogged streets that pauses for a dip in Lake Union, RTD is by far the wackiest, tackiest, least purely historical experience competing for your tourist dollar. But it is nonetheless required. (PRO TIP: If you’re willing to part with a $50 gratuity and the boat isn’t too full, the “captain” may let you drive.) I’m not suggesting you go spend every weekend tooling around the city on board an amphibious landing craft with all the other rubbernecking rubes in Starbucks sweatshirts singing along to Led Zeppelin songs and cheering obnoxiously when prompted by the tour guide/driver. But I am demanding you do it once, for a visitor’s-eye view of the city. (SEAN NELSON)