One of the deficiencies, if you can call it that, of Google Earth is that it doesn't list the interstate exit numbers as one of its many options for labels. Perhaps it's just us map-making geeks that even notice it but it's been a thorn in my side for years and years while I've been trying to digitize trail maps on Google Earth.
And for just as long I've been trying to get the
Department Of Transportation (DOT) to cough up their data in a publicly useable format – no joy. I'm not even convinced that I ever reached an official DOT employee. Now, I've found a source for the coordinates and have spent more hours than I thought it would take in producing Google Earth files for all the western states (where most of our available trails are located.