Reading the article on the new Airstream 684 in July's magazine, under "Lockers" it states that trailers and caravans can not exceed 7 metres on UK roads unless the vehicle towing them has a gross weight of 3.5.tonnes+. Is this correct? In the june issue of cc mag it says 18 metres is the maximum permitted overall length of a car and caravan outfit on UK roads so I'm confused. Looking at the buying pages, most 4 berth + caravans on the market have a shipping legth of over 7 metres so I'm really confused. Any ideas?