Simplify the following text for a Grade 6 native English-speaking person.
Original: All classified roads starting in the zone between the A1 and the A2 must begin with the figure 1 ( A137 , B1412 ) , etc , etc. .
Simplified: Roads which start in the area between the A1 and the A2 must start with the number 1 ( A137 , B1412 ) , etc. .