Wouldn't travel generally be considered challenging for people with autism or Asperger's, though? A quick Google on Asperger's +travelling reveals tons of "survival tips."
It really depends on the circumstances of the travel and the sensory and transition needs of the particular person with Apserger's or autism.
One of the possible symptoms of Asperger's Syndrome is "rigid adherence to non-functional routines". If a person with Asperger's is used to a very predictable daily schedule, and travel disrupts this (which it almost inevitably would), then I can see it being a huge issue. We never had a terribly regimented schedule, so this never became a significant problem for us. My son does hate it when someone changes plans or a schedule without telling him in advance, though.
Most of our travel has been done by car, and involves trips that end up at state or national parks, museums, and other types of places that he enjoys anyway. As far as my son is concerned, the trip itself is a great opportunity to either read for long periods, catch up on sleep, or ask questions and converse at length with us (while we are a captive audience) about all the new things he's noticing out the window, while still being in a controlled, familiar environment (our car) loaded down with pillows (a favorite sensory activity). He really enjoys going new places as long as he has someone else with him to help him navigate, and as long as the new places aren't disorientingly loud or too flashy/bright, and don't have smells that are too unpleasant to him. (He's considered becoming a perfumer at times just so that he has a fighting chance to get pleasant smells out into the environment). I think he'd hate air travel these days, with its long lines, crowds, loudspeakers, close contact with unpleasantly-scented people, and TSA checkpoints. Theme parks and other chaotic places are not favorites unless we choose dates carefully to minimize really oppressive crowds.
Kids who had greater sensory sensitivities and more rigid adherence to routines, or who had low receptive language, so that successfully preparing them for an upcoming trip would be difficult, would almost certainly be far more challenging to travel with.
