Hi Julie
Two years ago we stopped in Verona and Venice. At the time I didn't take the GPS locations. However this is a suggestion.
Venice
We stopped at Punta Sabbioni this is at the far end of the Lido di Jeselo. There are loads of campsites along this strip so if you want a campsite there are plenty of options. However, if you want Aire type parking then ignore all of these and just keep driving. When you get near the very end of the Lido there will be a sign to say ferry terminal only, ignore this and drive on past the ferry terminals along the side of the harbour where you will find secure motorhome parking. I think it cost 10 Euros. From there you can get the passenger ferry right into Venice.
https://www.google.co.uk/maps/@45.441417,12.421154,3a,75y,180h,92.79t/data=!3m4!1e1!3m2!1shD-jfjD9FpYQkpyroOPmCQ!2e0!6m1!1e1
Verona
There is a camp site Castle San Pietro on a hill overlooking the old town, and by the castle. However, the entrance to the site is quite small with low hanging trees. If you drive on past the entrance, which will be on your righ,t you end up at the castle gates, where you will need to turn around. We parked overnight on the road, along with a few French and others. No one bothered us. It is a pleasant walk down into town. When you drive to this location you have to go through an archway in a wall. It is a bit tight, but don't worry as all will be OK
This is where we parked/ slept. I know it doesn't look wide enough but it is.
https://www.google.com/maps/@45.448777,11.004238,3a,75y,90t/data=!3m4!1e1!3m2!1s6BH_MiU4Aozn0amPsQ_n0w!2e0!6m1!1e1
This is the camp site entrance!
https://www.google.com/maps/@45.450415,11.004468,3a,90y,86.11t/data=!3m4!1e1!3m2!1sHI3Bn7I0DSh2UJSj-jLkKA!2e0!6m1!1e1
Verona is my favourite Italian city. It is easy to walk around with a relaxed feeling. We also went to the opera in the Roman theatre which added to the experience immensely.
http://www.arena.it/arena/it/
I have attached a couple of piccies.
Hope this helps
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