I don't have a web page for it, but I can quote Wikipedia:
Quote: The international E-road network is a network of roads in Europe, numbered E1 and up. They cross national borders and are the responsibility of the United Nations Economic Commission for Europe (UNECE). In some countries like Germany, roads carry the European route designation beside national road numbers. Other countries like Sweden have roads with exclusive European route signage. Other continents have similar international road networks: e.g. the Pan-American_Highway in the Americas, and the Asian Highway Network.
The route numbering system, defined by UNECE since 1975, went through a major change in 1992 and is now as follows (text and layout slightly modified from the original for clarity of understanding):
1. Reference roads and intermediate roads, called Class-A roads, have two-digit numbers. Branch, link and connecting roads, called Class-B roads, have three-digit numbers.
2. In general:
* North-south reference roads have two-digit odd numbers terminating in the figure 5 and increasing from west to east.
* East-west reference roads have two-digit even numbers terminating in the figure 0 and increasing from north to south.
* Intermediate roads have two-digit odd (north-south) and two-digit even (west-east) numbers between the numbers of the reference roads between which they are located.
* Class-B roads have three-digit numbers, the first digit being that of the nearest reference road to the north, the second digit being that of the nearest reference road to the west, and the third digit being a serial number.
3. North-south Class-A roads located eastwards of road E99 have three-digit odd numbers from 101 to 129. Other rules mentioned in paragraph 2 above apply to these roads.
4. Class-B roads located eastwards of E101 have 3-digit numbers, beginning with 0, from 001 to 099.[/quote]
http://en.wikipedia.org/wiki/Internation...ad_network
German
Autobahnen have a different numbering system:
Quote: Odd-numbered autobahns usually run in north-south direction, while east-west autobahns have even numbers. Single-digit numbers indicate major routes of (inter)national significance, while three-digit autobahns are usually only significant to local traffic. For two- and three-digit autobahns the first digit roughly indicates the part of Germany that particular autobahn is located in. Within each block of numbers the numbers increase from north to south and from west to east.[/quote]
I live near in a region that hosts the southern end of A 1, the western end of A 6 and A 8, and two minor highways: A 620 and A 623. Our postal codes and telephone area codes also start with the digit 6.
http://en.wikipedia.org/wiki/List_of_mot...in_Germany