How are the childer with crowds?
I know Tiger and Mars would hate somewhere like Disney World, but I know both both tolerate and enjoy "real" places that they can leave with no pressure. Tiger specifically loves Haven resorts, which are laid out the same way in different seaside towns. He gets to stay in accommodation he recognises from year to year with the same style pools, amusements etc. Yet he gets to paddle in the sea and walk different streets with Mummy, Daddy and sis. I'm sure an RV would have the same soothing effect.
I'm sure you know that as you know them (and autism) far better than I ever will.
It sounds like a wonderful way to show them some of the country without stress. Except for you - where you do the same chores but with less space and more inconvenience.
At least that's how my Mum always viewed camping
We never "toured" but a park or beach, a picnic and a windy day were pretty much all we needed as a family. Even in this day and age they're young enough to feel the same. Kites, beachballs, frisbees, polysterene aeroplanes would keep us happy for hours. My bro was 4 years younger and would snooze in a blanket when necessary. Whatever I thought of him at the time he was never really a grizzly child.
Save important monuments for photo ops. You'll treasure them as they get older.
But you can take the photo and then all go play 2p slot machines for an hour.
Turns out that's kinda what Nanny and Grandad did for us the summers we spent in London. A few big occasions, some high profile photos
outside places they couldn't afford for us to lose interest in after half an hour; then feeding the pigeons, "beachcoming" on the Thames mudflats and sharing a Coke and a packet of crisps at the Royal Festival Hall. And always take a plastic boat and a spare pair of trousers. There might be a fountain. Probably forbidden but we did it back in the day and kids still do now.
Street markets too, unless they're too crowded.
Dunno bout there, but here, where there are large markets there is entertainment. Magic, juggling, fire-eating. Or sing-song salesmen and bright colours at least. Put something in the hat as it goes round, but for 4 it's far cheaper than a day ticket.
Sorry, I live worlds away in environment and distance.
Just working on what I know "my" boys love.
My advice?
Draw up a checklist of what they like, or what they could be
persuaded to like
Specify a distance.
Hit up TripAdvisor.