Core: Maximum speed with a trailer or caravan

With a trailer or caravan separate fixed maxima apply, regardless of what the sign allows for an ordinary car (Book p.229): - Inside the built-up area: 50 km/h. Not 80 — that is the most common mistake. - Outside the built-up area on an ordinary road: 80 km/h. - Expressway and motorway: 90 km/h, but only if the permitted maximum mass of the trailer or caravan is not more than 3,500 kg. Note the difference between 'outside the built-up area' and 'expressway': not every road outside the built-up area is an expressway. On an ordinary provincial road outside the built-up area it stays 80; the 90 applies solely on expressways and motorways. If the trailer or caravan weighs more than 3,500 kg, the 90 km/h exception lapses and 80 km/h also applies on expressway/motorway. This is not stated verbatim in the book — it follows from the law, which prescribes 80 km/h as a residual category (law-derived addition). One lane rule belongs here too: with a combination that is longer than 7 metres you may, on a motorway with three or more lanes, use only the two rightmost lanes — except when you have to move into position to turn (Book p.230).