64 to Luxembourg branches off. Then the highway climbs up from the Mosel valley and crosses the heights of the Hunsrück. On the other side of the Saarland border, at the Nonnweiler junction, one must leave the main carriageway to continue on the A 1, as the continuous route forms the A 62 towards Pirmasens. The last section of the A 1 to Saarbrücken is characterized by numerous curves, with which the Saar-Nahe-Bergland is crossed. At Illingen, the A 8 (Luxembourg-Pirmasens) crosses the Saarbrücken cross, the A 1 crosses the Saarkohlenwald and ends at the junction Saarbrücken-Burbach (150) in the development area of the Saarbrücken district Malstatt. The adjoining B 268 continues to the city center of the Saarland state capital. Congestion and speed limits The road has either two or three lanes each way. Congestion is possible around Hamburg, during holiday periods between Hamburg and Münster, between Dortmund and Cologne because of roadworks and especially around Cologne. During the rush hour the Cologne Beltway (junctions 98–104) is very busy (AADT 100,000-120,000). It is three lanes each way. The speed limit on the Cologne Beltway is mostly 100 km/h. Northbound between junctions 103 and 102 as well as between 101 and 100 the speed limit has recently been raised to 120 km/h. South of the Cologne Beltway the A1 has two lanes each way between junctions 104 and 107. There is a speed limit of 120 km/h northbound between junctions 105 and 104, otherwise this section has no speed limit. Between junction 107 and 109 the A1 and A61 run concurrently. The motorway has three lanes each way and a variable speed limit here. Overall most of the A1 has no speed limit. European Roads : Heiligenhafen – Autobahnkreuz Lübeck : Autobahnkreuz Lübeck – Autobahndreieck Stuhr : Autobahndreieck Stuhr – Autobahnkreuz Köln-Nord : Autobahnkreuz Köln-Nord – Autobahnkreuz Bliesheim : Autobahnkreuz Bliesheim – Blankenheim/Tondorf : Autobahndreieck Vulkaneifel – Wittlich-Mitte /: Wittlich-Mitte – Autobahnkreuz Wittlich : Autobahnkreuz Wittlich – Autobahndreieck Moseltal : Autobahndreieck Moseltal – Saarbrücken-Malstatt History The A 1 and A 2 were first planned in the 1920s. The interchange between the two (Kamener Kreuz) was one of the first cloverleaf interchanges in Germany, opened in 1937. 1930s The groundbreaking ceremony for the construction work on the section between Hamburg and Bremen was completed on 21 March 1934 at Oyten. After just two years, on 25 July 1936, the 71-kilometer section