I am very blessed that I will inheret about 100 acres in WV. Probably half of that is trees and half is pasture and hay fields. I have about 250 miles of which about 200 miles are highway to get there. I plan to eventually build myself a small cabin there.
Anyway on to your brainstorming. I see state/national parks/forests as stopping points along the way if needed. My reasoning is short term any staff is going to just lock the gate and head home but if the event stretches out then your going to have to deal with others who have the same ideas or the maintenance staff coming back. So I don't see them as long term options, more a resting place for some sleep or refilling the water jugs and such but then moving on.
I do keep a map with all theose locations in my truck as well as maps of each park/forest. Since my main bug out route goes in a zig zaz path along the highways if something were to happen and I need to take back roads I have started mapping out alternate routs and started visiting those parks and forests to get familiar with the roads and areas there. this also lets me get outdoors some and practice a little bit of skills and test some of my gear. I've found that some of the parks and forests have gated entrances and some do not. So little details like that may help if some event happens. I make these weekend family outings as practice bug out situations.