Translation:The distance is far.
"-nya" is a way to refer back to something already mentioned. It's commonly used similar to "him/her/its" "Her Dog = Anjingnya"
In this case, there's no person or thing mentioned prior, and it doesn't really make sense for someone to possess a distance. However, we can still refer back to something that may have been mentioned earlier and still part of the context of the sentence.
For example, The previous sentence may have been "I'd like to travel to Melbourne by bicycle, but I'll make a lot of stops." "Oh why is that" "The distance is far"/ "Jaraknya jauh"
So in this sentence, "nya" is translated as "The" where the makes it clear we are talking about a particular distance to a particular place, as opposed to just a general concept of distance.