Knocked this one up quickly this morning.
South side of Chicago, only 10-15 mins from centre of the city, lakefront position on an old steelworks site.
As you can see there's an existing four lane road going through the site, with space in the top left big enough for a national stadium (checked size compared to Chicago football stadium).
There's also a couple of interesting waterways to wot around, you could totally get the Yas Marina effect with Chicago flavour.
A couple of things to ignore: firstly there's a proposed housing development in the top area, and also for the sake of this fantasy track I guess you have to ignore the housing proximity. This is a deprived area and you could easily redevelop the housing especially bringing in jobs at the venue, hotel and bars &a restaurants.
I wanted to keep all the major roads in place, with only bridge construction and tunnel construction to change the use.
I also wanted to try and use parts of the existing dirt track layout in the top half of the site and I though they make for a cool start.
So here's the track layout, ANTI CLOCKWISE, start finish straight parallel to the pits on the top right.
We start with a long fast left into chicane, followed by another flowing long left and a hard right under the road bridge.
Then we work through the venue complex with a viewing bridge built over the track connecting the venue to grandstands only accessible to venue entrants.
We then have a long straight before a more street style complex of almost ninety degree corners built around a panoramic grandstand.
This is followed by a full acceleration left curve into a set of fast following esses before a short straight leading into a sharp hairpin opening out into the longest straight.
After the hard charge of the long straight, at the end of which we have another viewing bridge coming from the event venue, we go into another quick couple of turns before entering a short oval section broken by a Daytona style chicane leading onto the short start finish straight again.
We have two cut throughs to give shorter options marked in a slightly lighter grey.
I measured the pits against silverstone so there is easily capacity for 60-80 cars for something like a 24hr race.
I also marked in 4 car parks with connecting roads, you could have shuttle buses connecting grandstands, venue and car parks.