I am doing my very first long journey (short visits) trip around Europe in October.
I am wondering, what is the smartest way of organising public transport in cities I'll be staying in for roughly 3 days? Anything over I'd think a travel card is a must, i.e. like Oyster Card in London.
At what point does using buy-as-you-go get too expensive compared to buying the local cities' travel card? Is it appropriate for 2 night stops, or just more than that?
I only have experience with Australian public transport (awful in comparison) and London's public transport.
I will be visiting main cities only, i.e. smallest being Avignon or Frankfurt, where I expect paper tickets to be a thing I'll have to use. (or just walk)