Jogging and highways, a perfect combination?

Last weekend, a friend and I went for a jog in the forest south of Brussels, het Zoniënwoud / Forêt de Soignies. We had the idea to cross this majestic beech and oak forest NE-SW. So we did, but halfway this green lung of Brussels, there was something we had completely forgotten about: we found the Brussels/Waterloo/Nivelles highway blocking our path. This 2 x 4 lane bitumen strip of madness appeared to be too difficult to cross, and as we were - and still are - bold men, we decided to run along the highway until we found a device to overcome this problem. A bridge proved very helpful, although we had to run for 3 km into the Flemish region to use it. No big deal, an hour and a half later, we were having dinner, feeling proud about our approx 16 km of mud and rain and fresh air. Not bad.
There is one thing that intrigues me: when we were running along this highway, we were moving a lot faster than ín the forest. Of course, the surface/soil we walked on was better, but still.
I think it was the adrenalin running through our veins. Having a stroll one meter next to a frenzy race of cars and trucks, that was quite a thrill. Every 500 m or so we saw traces of impacts: when there is a crash of 1400kg metal, rubber, hydrocarbons and human flesh multiplied by 120km/h = a lot of destruction. Ah, the smell of danger, and exhaust fumes.
This weekend, I suggest we run along the landing strip of Zaventem National Airport, or the E40 to Gent,...

The heavens are the limit.