The U.K. has a long history with motorsports – most Formula 1 teams, for instance, call it home. However Formula E got into trouble with the locals in London for its previous races there (and the helicopters covering it), so it had to find a new venue.

Thus, Formula E chose the ExCel exhibition center on the east side of the city as its venue and the track was noteworthy for its configuration, which saw the cars running both inside the convention center and out.

It was a bit of an odd location and even Formula E wasn’t sold on it immediately, first trying to set up a track that would have seen the cars racing past Buckingham Palace and Trafalgar square. But as organizers dealt with the headaches that the local residents provided, they eventually decided to go for the ExCel Center, according to a recently released video by YouTube’s Chain Bear.

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Like a few go-kart tracks around the world, that allowed Formula E to do some fun stuff, such as run the track over two floors, and also meant that the event was less weather-dependent than usual.

The idea also presented issues, though. The FIA requires tracks to be wider than two cars at points so that passing can actually occur. It’s also very particular about safety and, more to the point, the track surface must provide a certain amount of traction.

The polished concrete that was originally there would have been too slippery for racing, so the organizers had to sand the floor down, taking 2.5 mm (0.09 inches) off the surface before spraying down emery (like an emery board for your fingernails) and sealing that in to make a track surface that was suitable for cars to race on. Indeed, the track is so grippy now that it actually hurts to run your fingers over it.

It’s all a fascinating look into how hard it still is to run a race in the heart of a city, even if the race cars aren’t quite as disruptive as a normal car.