The A82 Fort William to Glasgow road will be closed periodically today as road policing officers carry out investigations near Glencoe.
Fort William officers began at The Gorge from 8am, requiring a full road closure.
Motorists travelling on the West Coast trunk road are expected to face lengthy tailbacks as the road closure comes into effect.
However, officers are expected to reopen the route periodically to alleviate congestion.
Police say the investigation taking place is to do with a fatal crash from June and that the road will only be closed for 10 minutes at a time.
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