Any distance that you wouldn't want to travel every weekend - I don't think 3 hours is that big of a deal, so I wouldn't even class that as far away. For me, I think 5+ hours is long distance, and even that is doable every two weeks or so. For me, it's not so much how far you live from each other, but how often you get to spend time together. If you get to see each other every weekend or every two weeks, I don't think of it as long distance.
I'm currently an 8 hour plane ride (+trains and cars) from my boyfriend, which is 100% long distance. We haven't seen each other in 3 months and won't see each other for another month. Earlier on in our relationship, we were a 2 1/2 hour train from one another and it's wasn't a big deal at all!