Is it feasible to slip into the UK through Portsmouth for a day trip? I have an EU residence permit, but that won't cut it for a eurostar or some such popular travel method - I'll need a silly visa with the whole rigamarole of getting one. But could someone, in principle, just take a ferry from Ouistreham to Portsmouth and spend a day on the isles? Anons who've taken this fantasy method of transport, how tight is border security there? Do they scrupulously check your documents, or just a cursory glance looking for "EU" written somewhere on your ID?