By Air - Cancun's international airport is one of the busiest airports in Mexico, receiving frequent flights from the US, Canadian and European cities. From Mexico, you can fly to Cancun from Mexico City.
By Bus - You can travel to Cancun on a luxury bus from Mexico City - but the trip will take around 24 hours. Flying is the most sensible way to get to Cancun, unless you are on a budget, and don't mind the wait (and want to see the sights along the way). For local bus transportation within Cancun, see paragraph below.
By Car - Driving to Cancun is recommended only if you have a good reason to go by road - for example, you want to stop and see places on the way. If you are going to drive, keeping to the toll roads will speed up your journey.