you dont even have have to LAND at another airport for your ATP. Just go 50NM from point of departure.
Now my question is, and I have heard several differnt answers, how about landing at 3-4 airports. One being 50 nm from departure, and the other not being. FOr instance, I fly from one, go 50 NM, and hitanother 25 NM apart from the others. Is ALL of it X-C? I'd say not, but some say yes.