International E-road network

The international E-road network is a numbering system for roads in Europe developed by the United Nations Economic Commission for Europe (UNECE). The network is numbered from E 1 up and its roads cross national borders. It also reaches Central Asian countries like Kyrgyzstan, since they are members of the UNECE.

European main international traffic arteries are defined by ECE/TRANS/SC.1/384 which consider three types of roads: motorways, express roads, and ordinary roads.

In most countries, roads carry the European route designation beside national road numbers. Other countries like Belgium, Norway and Sweden have roads with exclusive European route signage (Examples: E 18 and E 6), while at the other end of the scale, British road signs do not show the routes at all. Denmark uses exclusive European routes, but uses also formal names for every motorway (or part of such), which the motorways are referred to, for instance in news and weather forecasts.

Other continents have similar international road networks, e.g., the Pan-American Highway in the Americas, the Trans-African Highway network, and the Asian Highway Network.

UNECE was formed in 1947, and their first major act to improve transport was a joint UN declaration no. 1264, the Declaration on the Construction of Main International Traffic Arteries, signed in Geneva on September 16, 1950, which defined the first E-road network. Originally it was envisaged that the E-road network would be a motorway system comparable to the US Interstate Highway System. The declaration was amended several times before November 15, 1975, when it was replaced by the European Agreement on Main International Traffic Arteries or "AGR", which set up a route numbering system and improved standards for roads in the list. The AGR last went through a major change in 1992 and in 2001 was extended into Central Asia to include the Caucausus nations. There were several minor revisions since, last in 2008 (as of 2009^[update]).

...
Wikipedia