OK, I'm not sure how to do the fancy profiles or maps, or embed pictures (if anyone can advise I'll try and edit), but I saw something saying GB might bid for the World Championships the other day, and it got me thinking about a fantasy world champs course in my hometown Bristol.
I reckon you could start next to the harbourside on Anchor Road, go up St Michael's Hill - which is about a kilometer that must be around 10% average gradient, with (considerably) steeper sections, through Clifton and across the Suspension bridge, then loop around the top of Ashton Court park (This is all fairly flat ) before the descent round the South of the Park (which is probably about three/four kilometers at an average of about -8% and not particularly technical).
Then back up Rownham Hill to the bridge - there's a link to a Strava profile below which says its 9% average with 16-17% section. Once you cross back into Bristol proper, turn left and descend down onto the Portway, which takes you underneath the Suspension bridge and back onto Anchor Road for the start finish - I reckon it's about 20 kilometers a lap, so eight laps, 16 kilometers of proper climbing, about 25 kilometers of fast descending, and the rest flat, all with a beautiful/historic back drop.
There might be a problem with using the bridge in two directions (and more to the point the approach roads, as the bridge itself is naturally split into two carriageways) especially if the field splits, but assuming you could overcome that I reckon it would be fantastic - no idea who would win either!
Some context:
Here's a map I made
http://friendfit.com/routeview.php?rtnum=75596&from=fitblog
A photo of St Michaels Hill
http://www.yourlocalweb.co.uk/images/pictures/16/38/st-michaels-hospital-161360.jpg)
A profile of the second climb
http://www.strava.com/segments/rownham-hill-short-bristol-670831
Some images of the Suspension Bridge:
http://www.google.co.uk/search?tbm=...1634l2774l0l4191l11l8l0l0l0l0l162l969l2.6l8l0