As our Reader informed us:

The traffic jam on the A4 stretches for 15 kilometres

And she adds: – From Jarostów to Kąty Wrocławskie.

This is the aftermath of a collision between a passenger car and a truck, which occurred at kilometre 165 in the direction of Wrocław. More about this in the Kąty Wrocławskie na sygnale service:

Kąty Wrocławskie na sygnale on the accident