Zagreb as the largest and the most important traffic junction in the country is both an origin and destination of many travels that take place over six (A1, A2, A3, A4, A6 and the future A11) motorway routes. They all finish or start on the lateral south road – the existing Zagreb bypass. This is the place where European corridors X, Xa and Vb intersect.

With the traffic load from transit traffic the bypass today takes over a great part of inner and origin-destination traffic of Zagreb. Some parts of the bypass have already become the town road on which about 70% of traffic is generated by the town traffic (especially the section between Jankomir and Lučko and at Lučko interchange). According to the traffic count data on the existing Zagreb bypass in 2009 the AADT (average annual daily traffic) was recorded of 54,542. Considering the accelerated development of the broader area of the town of Zagreb and Zagreb County we can expect a persisting traffic load rate in the forthcoming period too which leads to traffic conditions inadequate for the roads of high category. On the existing bypass there is a constant increase of AADT which means a significant drop in the serviceability level.