It's the Arch at the Porte St Martin which was built in 1674 and restored in 1988. It was ordered to be built by Louis XIV, in honour of his victories on the Rhine and in Franche-Comté. It was designed by architect Pierre Bullet. (source : Wikipedia)
I wonder if Louis XIV could ever have imagined the type of traffic which would pass around this arch today ... cars, vans, bikes and yes, motorised scooters!
Well check it out — there's a guy on a scooter! Your mentioned it made me look closer and realized he wasn't actually on a bike. Great scene for a B&W edit.