I've driven about 17 hours to a conference at the Stanley hotel. 8 hrs to Kentucky for the Waverly, and 3 hrs to Vicky. If it's interesting enough, I'll be there with bells on. (Planning a trip to Edinburgh, how far is that?)
I have gone 2+ hours before...a lot depends upon what is happening. how well documented the haunting is (i.e. how often does it happen, when does it happen etc)..how stable I feel they are...when they wanted us..etc