The picture shows one of the exhaust outlets of the Craeybeckx-tunnel that connects the E19 between Brussels and Antwerp to the Antwerp Ring R1. The outlet is situated some meters in front of my parent’s house, where I was yesterday to pick up some memories. When you drive some 100 meters in the tunnel towards the Ring of Antwerp, the green sight of the picture is what is laying above you. There is a little park that functions as a small green lung in the Antwerp suburb Wilrijk.
In the park, one hardly notices the outlets, which are now overgrown after all those years, just like the emergency exits and the exhaust outlets from the service shaft in between the two main shafts. On the pictures, the only thing that might bother some people, is that there is a need for some gardening. As you look at the videos though, you will notice how much sound is produced. That is a totally different picture.
The good news is, when electric cars will be the norm, both the sound and the black carbon-dioxide deterioration will be gone.