John Krasinski from his campaign with Hyundai. Credit: Hyundai When John Krasinski travels, he lets his instincts drive his itinerary. Case in point: One New Year’s Eve in Barcelona, the self-proclaimed “history nerd” followed the path of one of his heroes (Ernest Hemingway) to the London Bar. It was reserved for a party, so he hopped in and joined the festivities. “I believe the youngest person there was 80,” the 46-year-old actor told Travel + Leisure. “I ended up dancing the night away with 80- and 90-year-olds—it was one of my favorite nights ever!” Another time on a road trip through South Dakota, he found himself in the midst of the Sturgis Motorcycle Rally. “I’m so not cool enough to be a motorcycle biker,” he said.…