Hmm, around the Lake City area is in the middle of the huge hole between Superchargers in the U.S., as seen here:
www.supercharger.info, so the destination charging around that area is very nice.
As to the question you actually had about travel distances, there are a couple of ways to think about that. For a once way distance, where someone knows they are going to get to a Supercharger, so they are not hesitant to deplete most of the way, about 200 miles would be common. But for round trip situations like this, where people will be driving in and then using slower charging to get back out, it may be a little less, like 150 miles.
That kind of depends on how long people will be there to charge. If it's normally a 1-2 hour type of place, people may not want to have to wait for an extra few hours of charging to get back, so they might distance limit some. But if it's normally a long-ish 5-6 hour day of activities, then they will be able to charge all the way up anyway, so the full 200 mile trip each way would probably apply again.