Transport Scotland has apologised for delays on the A9 north of Inverness during a survey of motorists.
Wednesday morning's work on the southbound carriageway near the Kessock Bridge was part of the planning for improvements to roads in Inverness.
Some motorists took to social media to criticise the decision to do the survey during the rush hour after missing appointments and being late for work.
Transport Scotland said "important evidence" was gathered from the survey.
It will be used to inform the design and development of Inverness' A9/A96 Inshes to Smithton Link Road and A9/A82 Longman Junction Improvements.
A Transport Scotland spokesman said: "We appreciate that these surveys can cause delays and our contractors were monitoring the queues throughout the morning.
"When necessary, the survey was suspended to allow traffic to clear the area. In order to ensure that the data we gather reflects normal road use patterns, it is not possible to provide advance warning of the surveys.
"We want to thank people for their patience this morning and we apologise for the delay caused."
Councillors headed for a special meeting on controversial plans for the Coul Links golf course at Embo were among those caught up in the traffic, causing a delay to the start of the meeting.