I am flying through a tunnel with a distinct green emergency exit sign, which is common in many European countries. The road markings include a solid yellow line on the left, suggesting right-hand traffic. The clean, modern tunnel architecture and the specific style of the lighting and signage point towards a well-maintained infrastructure, likely in a developed nation. I suspect this is in Norway, given the tunnel design and the green exit sign style. I am moderately sure of this assessment.

then: forward

The tunnel walls are lined with white panels, which is very characteristic of Norwegian tunnel engineering. The yellow line on the road edge confirms right-hand traffic. The signage style and the specific lighting arrangement are consistent with major road tunnels in the Oslo area. I am fairly confident this is located in Norway. I will guess the E18 tunnel near Oslo.

then: guess