Los Angeles is the second-largest city in the United States (after NYC) and needs no introduction. It’s airport – Los Angeles International Airport – is perhaps one of only a handful of airports known internationally by its IATA code (LAX) – although some of Detla’s top flights are to John Wayne Airport. By some measures, 
Delta Air Lines is the largest airline in the United States, and it commands the largest market share at LAX at 19.76% (although not enough to be dominant). According to data provided by Cirium (an aviation data analytics company), these are the busiest routes to Los Angeles.