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Traffic jamSwitzerland

Learn traffic rules with clear explanations and visual examples in our illustrated book, designed to make studying simple and engaging.

Traffic signs
Traffic rules
Switzerland

68. Traffic jam

A traffic jam is a situation where traffic becomes heavily congested and vehicles move very slowly or stop for extended periods. Traffic jams are commonly caused by high traffic volumes, accidents, roadworks, lane closures or poor weather. Drivers should remain patient, keep a safe distance, avoid unnecessary lane changes and watch for motorcycles, emergency vehicles and sudden braking. Where lanes merge during congestion, local rules may require drivers to use a zipper-merging system.

Traffic jam
Traffic-congestion warning sign with additional traffic signs. (Switzerland)
Wikimedia.org • Marc Mongenet • CC BY-SA
What is a traffic jam?

A traffic jam occurs when traffic becomes congested and vehicles move slowly or remain stationary because the road cannot accommodate the normal flow of traffic.

What causes traffic jams?

Common causes include heavy traffic, accidents, roadworks, lane closures, bottlenecks and poor weather.

How should you drive in a traffic jam?

Keep a safe distance, avoid sudden braking and unnecessary lane changes, and remain alert for changing traffic conditions and emergency vehicles.

Should you change lanes frequently in a traffic jam?

Usually not. Frequent lane changes can disrupt traffic flow and increase the risk of collisions. Change lanes only when necessary and safe.

What is zipper merging?

Zipper merging is a system where drivers use all available lanes until a lane ends or becomes blocked and then merge alternately into the remaining lane.

Should you leave space for emergency vehicles in a traffic jam?

Yes. Many countries require or recommend drivers to create space for emergency vehicles when traffic becomes congested or stationary.

1 Switzerland 2 Motorway 3 Expressway 4 Residential area 5 Zone 6 Speed limit 7 Minimum speed 8 Footpath 9 Bike path 10 Shared-use path 11 Tunnel 12 Pedestrian zone 13 Customs 14 One-way traffic 15 Slope 16 Bus lane 17 Bus stop 18 Dead end 19 Stop sign 20 Give way 21 Roundabout 22 Priority road 23 Road narrowing 24 Priority over oncoming traffic 25 Give way to oncoming traffic 26 Pedestrian crossing 27 Railway crossing 28 Mandatory direction 29 Turn prohibition 30 School area 31 Overtaking 32 Crossing animals 33 Slippery road 34 Rockfall 35 Aircraft 36 Curve 37 Chevron 38 Wrong-way driving 39 Roadworks 40 Crosswind 41 Height limit 42 Width limit 43 Length limit 44 Weight limit 45 Intersection direction sign 46 Priority at the next junction 47 Traffic lights 48 Traffic lights warning 49 Pedestrian lights 50 Road markings 51 Junction layout 52 Driving licence 53 Location marker 54 Road number 55 Countdown markers 56 Traffic mirror 57 Emergency telephone 58 International border 59 Pedestrian underpass 60 Cycling route 61 End of restriction 62 Parking 63 No parking 64 No stopping 65 Parking disc 66 Reversing 67 U-turn 68 Traffic jam 69 Detour 70 Uncontrolled crossroad 71 Road surface 72 Exit 73 Information point 74 Horse riding 75 Emergency exit 76 Runaway truck ramp 77 Radio service 78 Oversize load 79 City limit 80 Hospital 81 Parking garage 82 Passing place 83 Pedestrian overpass 84 Axle weight limit 85 Licence plate 86 Charging station 87 Dangers 88 Weather 89 Turn on red 90 Pedestrian 91 Cyclist 92 Moped 93 Motorcycle 94 Car 95 Truck 96 Bus 97 Police 98 Ambulance 99 Tailgating 100 European emission standard ...