[jerf]

I drive through this twice a day:

http://maps.google.com/?ie=UTF8&ll=42.505215,-83.758199&...

It's a triple roundabout with a highway bridge separating two of them. The internals are arguably simpler but there are more entrances/exits than the magic roundabout.

For bonus points, check out what state this is in.

(I use Bing because last I checked Google still doesn't have a good satellite view of this, despite it being several years old now.)

[jrwoodruff]

I've been through that intersection! Let me tell you, coming off the highway expecting a normal intersection and getting dumped into that is pretty crazy. Not sure why they chose that design... Crazy MDOT.

[jerf]

If you sit down and try to draw the traffic light situation for that set of roads, this is actually a better solution than anything else I've been able to come up with. All the traffic-light situations I've mentally drawn out deadlock during rush hour with reasonable assumptions about people ending up in the middle of intersections accidentally as the light goes red, and have terrible throughput by comparison at all times of day. Presumably the actual civil engineers came to the same conclusion, only with better numbers and models. I can not imagine that was an easy sell, they must have had a rock-solid case.