Luna Park emerged on the north end of Alki Beach during the golden age of American amusement parks. Billed as "the Nation's Greatest Playground on the Pacific Coast," the park introduced the city to a host of novel attractions. Pleasure-seekers rode shimmering horses, thundered down the roller coaster, and marveled at daredevils and sideshows. There were games to be played, prizes to be won. Thousands swam in the waters of its natatorium and twirled...