Simplify the following text for a Grade 5 native English-speaking person.
Original: For example , the main road from London to Edinburgh is called the A1 , the `` A '' in Britain indicating a first class route ; this is classified as being more important than `` B '' roads .
Simplified: For instance , the main road from London to Edinburgh is called the A1 . The `` A '' means it is a first class route .