I would say you need to at least 1 sit down meal, stay overnight or some other major activity within whatever area can reasonably designated as “there”.
For example, I did not go “there” to Chicago when I flew into O’Hare and then drove an hour out to some office park in the suburbs. I was “there” in Nashville when we stopped over and had a bite to eat at some restaurant.
I’d say you’ve “been there” if you’ve been able to see it from ground level, outside a transit hub (so not just an airport layover). If you’re on a road trip and spent 4 hours driving through Kansas you’ve been there, even if you didn’t get out of the car. The act of driving through it and seeing the lay of the land qualifies. I have been to Italy (spent 2 weeks there) but have not been to Germany, despite a layover in Frankfurt.
I had to spend a day and night in the Casablanca airport. I don’t care what anyone thinks, I’ve been there.
If my visit is one of just passing through, I had to have been there enough to have needed a map, directions or a GPS.
That means that driving I-80 through Illinois doesn’t count as being there, but popping across the boarded from Illinois to Wisconsin in order to find a specialty shop, and needing directions or a map to get there, does.
Feet on the ground is best, with some credit for driving through on local roads. Transit hubs are a bit iffy.
I don’t think that simply having been born someplace counts for having been there. You have to be self-aware at the time of your visit.
I’ll give it to you…you’ve been there. 
I count “being there” as having seen enough of a place to form an impression of it that would not have changed significantly if you had stayed longer.
Well…I’m disappointed that I can’t claim to have been in Hawaii after this thread. I spent about two hours there…ate, and used the bathroom. But my arrival and departure was by plane, and the restaurant and bathroom were in the airport instead of a fast food joint.
But I’m still going to tell friends who bring up the state that I’ve been to Hawaii, but only to change planes…'cause it’s fun to see how long it takes them to ask where I was going. 
-D/a
I count it so long as I’m on the ground somehow, whether that’s on foot or in a vehicle.
Feet on the ground and away from the airport or station or highway in/on which you arrived. You also need to interact with the environment/locals in a way that lets you see or experience something that is reasonably distinctive about the locale, even if it’s just walking down the street.
In the area, on feet or not.
Everything else is just travel wankery and has no end, as in ‘you haven’t really been there unless you’ve been to X/done Y/eaten Z/stayed for A’ etc etc.
Otara
I would say airports don’t count. But then I can’t count Iceland and Romania. So screw it, I’ve been there.
If you just stay in the airport without going through customs and leaving the airport, it doesn’t count. Otherwise, I could count several more countries whose airports I’d been to without going through customs. But to be honest I don’t count them. It isn’t the same as really being there. Of these, the closest I ever felt to being in the country was at the Zurich airport, where you could look out the terminal’s windows at the meadows of Kloten stretching away toward the foothills of the Alps. I’ve seen Switzerland up close, but I still don’t claim to have actually been there.
Interacting with the place is actually not a bad one, but I selected other.
It’s when I get a feel for the place, draw from it’s resources, start to know it as one may start to know a person as opposed to know about a person.
As such there are places I have spent time at in the past but still don’t really feel like I have ‘been there’, but just brought my protective bubble along and chose to live in there while in the forien land.
Y’know, I could make a distinction in the part of driving through (cities and states/provinces/counties) – if I shoot straight through without getting off the Interstate/Freeway/Motorway, pausing only at designated rest stops and exit-ramp Comfort/Holiday/Fairfield Inns, I didn’t really visit. If I get down on the local streets, wait at traffic lights and pedestrian crossings and behind school buses, make wrong turns and have to go around ten blocks to get back on route after asking for directions, I may count it even if it was not a destination per se.
Oh.
In that case I’ve been to Massachusetts, Florida, and Maryland.
(I have high standards for being self-aware.)
In it is airspace.
I only count it if you have feet on the ground and have done something significant unrelated to travel or fulfilling basic needs (eating, toilet) in the process of traveling.
I don’t, for example, count myself as “having been to” Ethiopia, although I spent a couple nights in an Addis hotel changing plans. All I did was get in a van, go to a hotel, eat a hamburger in the hotel dining room and pass out. I think one of the days, I was able to spend half an hour on the street watching people go to work while I waited for the airport van. I know nothing more about Ethiopia than I would by watching a YouTube video, so in my mind it doesn’t count (though I will say “I spent two nights in Addis” if it comes up).
I took a train across the US, and don’t count any of the states I passed through- even the ones where I went on the platform to buy snacks. But I do count my layover in Chicago because I was able to wander around a little bit, see some sights, and talk to some Chicagoans.
Feet on the ground — absolutely. The only modality that genuinely feels like “being” in a place.
Only driving through — Hard for me to say… kind of a fuzzy criterion. What about only driving through and pulling off the freeway to buy gas or iced tea?
Flying over — don’t be ridiculous.
Being born there and leaving before memories formed of it — Yes, I still count that as really being there! Especially if you started walking before you left (again, the foot on the ground criterion being the gold standard of being there).
I see kanicbird already covered that. Well, I had exactly that experience in Indianapolis—pulling off to buy gas, then driving through city streets at dusk, and needing to pull over at McDonald’s to ask directions back to 70. I counted that as the one time I “was there” in Indianapolis (and I hated it). I experienced something similar at dusk in central Santa Fe, on the way to Abiquiu. Except that I loved my brief glimpses of Santa Fe, which became especially beautiful in the evening twilight, and ever since have always wanted to return there.