Man, on Friday I had to use a two-lane roundabout (in the U.S.) for the first time, and I'm lucky to have gotten through it without a major accident ... though I ticked off a few people and rightfuly got honked at.

Roundabouts are popping up all over the U.S. - replacing stop signs and stop lights - and EVERYONE in the U.S. needs to take some time to learn the right way to use then - especially a two-lane roundabout.

http://www.wsdot.wa.gov/safety/roundabouts/

My short lesson on how to use a two-lane roundabout is ...

1. Only use the outside lane if you are doing an immediate right turn. Hug the outside (right side) of the turn, turning into the right-most turn lane.

2. Head for the inside lane (when safe to do so), and when ready to exit use the left-most turn lane, but be watchful of knuckleheads like me who don't know the right way to use them!!!

Its really pretty simple IF you know how ... yesterday I clearly didn't know how. Sigh.

It's even more fun to jet to the UK, jump in a rental, and take to the roads - drive on the left side and deal with roundabouts. Driving on the wrong side was the easier task...

we are seeing more and more of these in Minneapolis and so far so good.people are getting used to them and some even are brave enough to go into the outside lane with someone on the inside and not use it like another form of stop sign.
the only problem i have had is that people don't obey the 15MPH sign as you come up to it.that throws off the people trying to drive into the round about who think they have time to enter only to have speeder blasting thru.

hikermore... worse than that, try the left side of road thing with a motorcycle... at least with a car you have the steering wheel on the right side to remind you something is different...quickly learned the Japanese phrase "baka gaijin"

Few US drivers know how to deal with a roundabout. The two-lane variety are dangerous in England and downright scary here.

We have a Diverging Diamond being constructed locally. If you've ever driven on one, I'd be interested in hearing how well it works.

HERE is what Wikipedia has to say about it.

-Jason

Tough. They're the ones that built it.

I'm driving as slow as I need to in order to locate and track all the moving pieces and well as the stationary route & guidance. If someone designs a road course where there are things moving at widely divergent speeds and angles it may take a while to find them all and track where they're going.

The stationary bits are going to be a lot faster on the second try but there is still going to be a problem of find all the moving things & estimating their trajectories.

I can't wait to read the first NTSB report (or relevant safety agency) after a major crash. Somebody needs to spend as much effort on human factors analysis and they do on flow rates.

We've had roundabouts in various areas here for at least 5 years. My trepidation level has gone down with experience - and we have the safest drivers in the country according to several insurance companies. Fortunately they aren't used for arterials but mostly for residential feeder streets and at shopping centers.

The divergent diamond looks like a nightmare. We already have people driving the wrong way on the interstate sometimes and that's with NO confused construction to scramble their perception of what's correct......

You should try the Magic Roundabout in Swindon, UK.

Magic Roundabout.

We're getting one at exit 407 on I-40. The only benefit I can see to it is that the left turns can be un-signaled. Other than that, they could accomplish the same thing by rolling back the last change to the way it was before and posting signs well back from the interchange as to what lane does what.

EDIT:

It was a standard diamond. They changed it to a partial 270 degree diamond.