The Federal Roads Office is warning of heavy congestion throughout February, especially on weekends.
Expect slowdowns on routes to winter sports resorts and on major autoroutes.
The Winter Olympics, starting next week in Northern Italy, is expected to add to the roads pressure.
Hot spots include Zurich, Bern, Basel, Lucerne, Chur and Lugano, plus the Gotthard and San Bernardino tunnels, the Bernese Oberland and Valais.
Drivers are urged to stay on the autoroute during traffic jams out of consideration of local residents.
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