A police operation has taken place on the A75 in a bid to trace witnesses to a crash which claimed three lives.
Police have renewed their appeal for crash witnesses
Luke Shearman, 16, Mark Johnston, 17, and Bethany Jane Secker, 20, died in the accident on 5 November.
Dumfries police returned to the scene of the crash to stop and question drivers in a bid to trace more witnesses to the collision.
Insp Linda Currie, who led the operation, said they were still trying to establish the causes of the crash.
"It is important that we speak to as many people as possible in order to piece the events together," she said.
Police are particularly keen to trace any witnesses who may have seen a red Nissan Almera, blue Renault Megane and blue Citroen Saxo in the area at about 1500 GMT.
These cars are thought to have travelled from the Newbridge area down Glasgow Road to the roundabout at Lochside.
It is then believed they headed west along the A75 Dumfries bypass, up the Glen to the Drummore roundabout and back towards Dumfries.
Anyone with information should contact police or the confidential Crimestoppers phoneline.