The U.S.-Mexican border is 1,933 miles long. It is a tough land full of deserts and mountains. And it can be a dangerous area populated with gangsters and smugglers. It is also an area that millions of people cross every year to illegally reach the U.S. Luke Dittrich is a contributing editor for Esquire and is walking the entire border for a year-long series for the magazine. Robert Siegel speaks with Dittrich about the first part of the series that appeared in the May issue of Esquire.