For the 2018 edition of Condé Nast Traveler's Readers' Choice Awards, editors tried something a little different. Instead of a single master list, this year editors split one of the biggest rankings, the world best cities, into two: the world's best small cities, and the world's best big cities. In the category of small cities, Mexico's San Miguel de Allende took the top spot, followed by Salzburg, Austria and Lucerne, Switzerland. The winners are based on the results of 429,000 surveys. Click through to see the winners of the world's best big cities 2018.