This week brings us to the outskirts of Paris, where we see what happens when the French need to build an interchange between two partially underground autoroutes:
This is the interchange between the Autoroute 14 (running northwest-southeast in the map above) and the Autoroute 86, the Paris Super-Périphérique (second beltway, running southwest-northeast in the map above).
The interchange is unusual in that both autoroutes are partially underground at this point — the A14 in the Tunnel de la Défense, which travels under the La Défense skyscraper district northwest of the City of Paris proper, and the A86 which heads underground to avoid additional disruption to the commune of Nanterre.
