Planning a 3 week trip (with an RV) on the east coast

Thanks all! We'll consider all suggestions. It really opens up a lot of new things when hearing the perspective from locals or simply north Americans.

Do any of you guys have suggestions for what to do (we don't mind an activity now and then) or see in Florida? Cuz for us we know a lot now what we can do in Washington, Virginia and north Carolina. But the other states ate more like a blank page still.