I had to go to WolframAlpha to calculate some details and find out exactly where I've been that is the farthest...
Looks like we have a winner! London is the furthest I have traveled from my home!Bozeman, Montana TO Belfast, Northern Ireland: 4261 miles
Bozeman, Montana TO Leicester, United Kingdom: 4498 miles
Bozeman, Montana TO Stratford-Upon-Avon, United Kingdom: 4502 miles
Bozeman, Montana TO London, United Kingdom: 4583 miles
Your turn everyone!