By Jamie Lauren KeilesJan. 5, 2021, 5:00 a.m. ETListen to This ArticleAudio Recording by AudmListen 49:48To hear more audio stories from publishers like The New York Times, download Audm for iPhone or Android.They came to Dubrovnik by cruise ship or Ryanair — members of a new hypermobile class of tourist, who traveled for cheap and didn’t stay long. They’d seen its walled Old Town on “Game of Thrones,” and they wanted to be there themselves, so they went. Venice, Barcelona, certain beaches in Thailand — these places had all faced their own “overtouristing” problems, but even by this standard, Dubrovnik was extreme. On busy days, tourists could outnumber permanent Old Town residents about 6 to 1. With a main thoroughfare less than a thousand feet long, this pressure on the city’s charm was overwhelming. By 2017, tourism had so overburdened the Old Town that UNESCO was threatening to revoke its World Heritage status. Mayor Mato Frankovic set out to save his city by sabotage, capping passage through the gates at 4,000 daily visitors and functionally banning new restaurants. Nevertheless, the tourists kept coming.But then, around March 2020, they stopped. After the Diamond Princess debacle, no more cruise ships appeared in the port. Airplanes were grounded, then took flight again — ending an age of quick and easy travel and ushering in a new, slower one. Pandemic travel was arduous and impeded by knotty, sometimes contradictory governmental guidelines. To travel under these conditions required an unhinged urge to take flight and a bureaucrat’s eye for parsing fine print. Brian Kelly, the founder of a website called The Points Guy, had both — plus a few million unused frequent-flier miles. This was how, on Saturday, Aug. 7, he found himself heading from New York to Dubrovnik, to see the walled city with nobody there.