>>1079317In Europe there are dozens of cross-border railways and trams, though this is made possible by free movement of people; just have a valid identity card with you, and between some countries just a driving licence or social security card with your picture is accepted.
Pic related, TILO, Swiss-Italy regional railway system. Used often when I spent vacation in Como-area.
Nothing special, only ''border thing'' they have is just legal notices for both countries in the train for example if you have to be fined or don't have a valid ticket, and before crossing the border there's just an announcement saying you must have a valid travel document (identity card is fine) with you and you must have nothing to declare.
In Denmark-Sweden a driving license is fine for crossing the border. Seems crazy for my mind.