In Germany can I travel by ferry? In which countries can I travel by ferry? Why do some rental companies forbid a ferry ride with the rental car? Can I use a ferry with my rental car? Does the border crossing with the rental car cost extra? How do I register my border trip? Can I drive my rental car across national borders? Driving abroad with a rental car: how does it work? Do border crossings cost extra? Can I travel abroad spontaneously?