Heavy traffic is expected 6 and 7 July on European highways as drivers travel to holiday destinations.
Long bottlenecks are expected on motorways to and from Brussels and on the city's ring network.
Belgian insurance agency, Touring, expects heavy traffic heading south on Friday afternoon and throughout Saturday.
Touring advises vacationers to leave on Sunday, which is classified as 'green' and "the best day to travel." The agency does not anticipate any problems in the returning directions.
Both Touring and travel assistance company VAB warn that the Tour de France will cause major traffic problems in Belgium, and therefore recommend alongside the police, to avoid travelling by car to Brussels on 4, 6 and 7 July.
Wallonia’s construction industry annual leave begins at noon on Friday and will also bring its share of cars on holiday roads. There could be queues on E40 Brussels-Côte and E411 Brussels-Ardennes, near Brussels, Liege, and Antwerp.
In France, traffic will be difficult in the sense of departures: red is expected on Friday afternoon and into the evening around Paris, and 'red' is announced on Saturday around the French capital. Elsewhere, busy traffic is expected with some bottlenecks ('orange').
Touring also reminds motorists that as of 1 July, the Crit'air sticker is required on the Paris ring road and in several other French regions.
In Germany, queues are expected in the departing directions, particularly on the northern motorway to Scandinavia, in the south near Hamburg, around Nuremberg (A3/A9), on the Munich ring (A99) on the A8 in the direction of departures and in Austria (A10 Tauern and A13 Brenner).
In Italy and Spain, Saturday is announced as 'orange' while in Switzerland, both Saturday and Sunday are classified 'red'.
In Italy, heavy traffic is feared on the A22 Brenner - Verona, Milan and around Florence, Rome, and Naples. In Spain, traffic jams are expected on the A7 France - Barcelona - Murcia and around Madrid.
The Brussels Times
