Hey - that’s not what I intended at all. I acknowledged the note about how US roundabouts are limited to ‘stay in lane’ variants only.
It does limit their utility for a wide range of junction types. Which is why it seems unlikely to our European roundabout-attuned sense of what a roundabout is for.
I have limited experience with US roundabouts. There was one I used daily on my way to and from college in the late 1980s that was notable in that it was the only one I ever saw in San Diego County in my first 25 years of living there. There’s one I use when I take my daughter to certain appointments here in L.A. Both of these are in residential areas. But anyway, all of them I can think of, without exception, have connected three or four or five two-lane roads, so they only ever had a single entrance lane at each road. I can see how the larger model would work with two-lane entrances, and how the signaling system and lane-change timing would be vital for such larger-scale intersections. I have no doubt Americans could eventually get used to it, but at least in the SoCal cities I frequent, they just don’t really have them on multilane roads, so the vast majority of American drivers would need a class to learn how to do it.
Our city’s traffice circle was infamous. It had three lanes entering the roundabout and only the outer lane was dedicated to exiting, so you had to change lanes at some point.
The city finally overhauled the circle and now there are two lanes entering and two lanes exiting, but the inner lane can continue around the circle.
I know people who AVOIDED it, using the outer circle (some with stoplights, some wothout), going from PCH (Hwy 1) to Ximeno or even Lakewood Blvd. The outer circle section between the southbound Hwy 1 re-opened more recently— it used to be closed off for a couple of decades.
See you and raise the Haymarket Roundabout in Melbourne, right near where I work.
Four major roads, two tram lines, traffic lights, and is between three hospitals (Royal Melbourne, Royal Women’s, and the Peter Mac Cancer center) and the University of Melbourne. Oh, and they’ve just built a train station nearby.
“Roundabout of death” redirects here.
This is, of course, the proper way to negotiate a roundabout:
(I nicked that from the old thread at TOP - there’s some good roundabout porn in that one - a link here to the top of the thread:)
Growing up in the east Bay Area, I didn’t have a lot of traffic circles to contend with. However, as I did go to Berkeley quite frequently I did have to contend with this rather infamous example:
In the center is an ornate fountain (that’s only intended to be viewed from afar as there’s no pedestrian access).
The map doesn’t do even really do it justice. I must have driven or ridden in a car through this circle over a thousand times when I lived in that area, and it was never not filled with some sort of excitement as nobody seemed to ever know how to contend with it.
To make matters more interesting, the Marin Ave leg in the upper right side of the map is an extremely steep grade that’s barely wide enough for the two-way traffic it supports (never mind all the blind driveways on either side):
Looking at Marin Ave in Google Street View, it looks like at some point the city changed the intersections so traffic going uphill has priority (only downhill and cross traffic appears to have stop signs). That’s a good thing. My first car was a manual transmission and I got really good stopping/starting from hills without rolling backwards from having to contend with this street and its uphill stop signs placed on steep grades. 
Here’s a brief history of this roundabout:
This is near where I just moved to. Some engineer in this part of Missouri apparently really likes roundabouts/traffic circles.
Here’s a similar one near me:
The big one in the center has been there for as long as I can remember, but the two smaller appendages formed after that area began to get built out more. (Which you can see with all the dirt areas being leveled out there.)
Here’s the fun* one (sort of) near where I live:
*and by “fun” I mean festooned with traffic signals & challenging to circumnavigate on foot. The traffic squares(?) (e.g. Mt. Vernon) aren’t much better (e.g. “no, I wanted to go straight, there! Aw damn it”)
I’m reminded Aaron Sorkin was inspired enough by its notoriety that he penned two very similar exchanges about it in The American President and The West Wing.
The American President:
SYDNEY
I got stuck on DePont Circle. I can never remember which lane I’m supposed to take. Then I got cut off by this idiot cab driver who starts screaming at me like it’s my fault.
SHEPHERD
Hi, Syd. Get stuck on DuPont Circle again?
SYDNEY
It’s not funny. I hate that place. Can’t you declare it a Federal Disaster Area or something?
SHEPHERD
I’ll look into it.
The West Wing:
SAM
What are you doing here so early?
LEO
Trying to avoid the protesters. Metro police closed a four-block radius around the World Bank and made Pennsylvania Avenue one way from M to 21st. Seventeenth and 15th are closed to Independence Avenue and Constitution’s closed between 23rd and the Ellipse.
SAM
Did you take Dupont?
LEO
Dupont had two turns closed off with metal barricades and cop cars. So, I took P to Logan
Circle, which was also blocked. So, I made a U-turn and doubled back to get on 16th, where
there was a police cordon around the National Geographic Society.
SAM
Who has a problem with the National Geographic Society?
LEO
That’s exactly what I want to know.
Indulging my almost harmless search for unrealistic motorcycles
It isn’t quite beautiful but it has something.
Oh, you sweet summer child; to some, “conversations” like this one aren’t ever meant for actually listening and learning, regardless to the OP’s benign enough intent.
It’s an endless opportunity to show everyone else how superior they are.
Who knew that “roundabouts” would spark the longest and most contentious thread on “Motors”. Now I dare not bring up “jughandles”, sort of a street level off-ramp that I’ve experienced in New Jersey.
AKA - Michigan Left. They’re mostly OK. Keeps traffic signals shorter at major intersections by eliminating the protected left turn movement. But you need enough room for the boulevard to begin with. 
I love Michigan left turns. So much safer than traditional left turns.
Here in Valenica, CA there are a few jughandles (more recently developed areas), but only of a type that are not configured for a left-hand turn. They are simply meant to siphon off traffic that wish to make a right-hand turn. Oh, well. Still.
