Food & Wine The World’s Fair Kicks Off in Milan 145 countries. 12 million square feet. NPR’s Sylvia Poggioli takes us inside Expo Milano 2015, the world’s biggest (and longest) "dinner party." Read or listen to Sylvia Poggioli on The Salt at NPR. Share Written By Sylvia Poggiolo for NPR June 30, 2015 Share your favorite recipe, and we may feature it on our website. Join the conversation, and share recipes, travel tips and stories.