What's particularly crazy about this interchange is that there is going to be a second, elevated peanut roundabout that's rotated 90 degrees, for buses to use: https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg...

Hey all, I'm the author of this game. I didn't expect to see it on HN! I wrote it to add some fun to all the conversations happening in the local forums about this roundabout. They've been heated at times. And, yes, this roundabout is right next to the Kirkland Costco.

I definitely agree with all the critiques of the gameplay - and I have about 100 more. I cut it down to the bare essentials to get it done while it's still relevant in the community. I wouldn't even call it an MVP. I probably won't update this unless there is some greater need. Though using Godot with Claude Code was a blast so I'm motivated to do new stuff there. I've been building solutions on Unity/DX/Unreal for over a decade - Godot was such a breath of fresh air!

So many comments talking about how straightforward some roundabouts are, but I think you guys are confused. Roundabouts are never straightforward, you're thinking of a normal road.

I'm used to roundabouts but I find the game difficult. Even if you made a basic roundabout I'd still crash a lot. 1) The car wants to go too fast on it's own. 2) The third person perspective is nothing like real driving where you simply yield to traffic on the left (or give way to the left for us down-under folks).

If it's meant to be an argument against roundabouts then it's a straw man.

I've been driving roundabouts for decades, and think they're great - they really help with traffic flow. I've never found them confusing.

I had to drive this specific Kirkland roundabout the other day, and ended up missing my offramp and going in completely the wrong direction. It's the most confusing roundabout I've ever seen.

The best part about Kirkland Roundabouts is that they come in a handy family-size 24 pack.

I'll let myself out.

about the gameplay specifically:

- have a mute button for the background music.

- there should be a gas pedal and a brake, rather than the car going forward at a constant speed unless I hit the brakes.

- the car should go straight, unless I turn. if I don't do anything near the exit of a roundabout, sometimes the "default" behavior is to exit the roundabout, sometimes it's to turn and continue within the roundabout.

frustration with the last point was enough for me to give up trying to play it. I'm sure the LLM that vibe-coded this thinks the controls make perfect sense, though.

in general:

is this trying to make a point of some kind about the design of the interchange? the "Inspired by online discussions of the Kirkland roundabouts" text sort of hints at that but it's unclear how.

is the point that it's overly complicated? or is the point that it's actually not that complicated, in response to people criticizing it? I can imagine it going either way...but the poor controls mean that it's not really effective at making either point.

different roundabout / intersection types would make this much more interesting. I've driven through the "diverging diamond" interchange of I-5 in Lacey [0] before, and it was a bit confusing the first time but now doesn't seem any more complicated than any other busy highway intersection. or, add a before & after comparing the old Kirkland interchange design to the new roundabout.

0: https://wsdot.wa.gov/travel/traffic-safety-methods/diverging...

That combination of soundtrack and graphics reminds me of [1]

[1]: https://en.wikipedia.org/wiki/Rock_n%27_Roll_Racing

A town I grew up in went absolutely crazy with roundabouts over the last 10 years or so. They built them everywhere. Most are pretty straightforward and they simplify traffic a ton but there were some bad design choices made.

Take this similarly confusing double-roundabout for example https://maps.app.goo.gl/VTSrSWsBGnsYyzKU6

There are accidents here almost every week and when an out of towner comes off the interstate to get some gas at Sam's Club (where I used to work) I had to try and explain to them how to get back onto the interstate...

I might try to clone this project idea, it was fun to play!

They also proposed a peanut style roundabout with a *train track going through it* that thankfully has not been built yet https://media.conwayarkansas.gov/media/documents/project/85/...

There's one installed a few years ago north of it where 132nd goes under the freeway. It used to have 2 lights to get through under the freeway. Now there are 2 roundabouts. I never have to wait anymore. It's a big win.

That is a very basic roundabout. I was expecting by "magic" that you would have to go round some part in reverse (clockwise for US left-hand driving). This is nothing compared to the original "magic" roundabout of Swindon, Wiltshire.

This interchange might have been better off using a diverging diamond interchange layout [1]. While not a roundabout they are "magic" and we should use them more often.

They just look confusing because at some point you are effectively driving on the wrong side of the road, but are extremely efficient. My daily commute includes one that cuts a few minutes off what it once took to negotiate the previous traditional interchange.

[1] https://en.wikipedia.org/wiki/Diverging_diamond_interchange

I love roundabouts. I have no clue what on Earth compelled them to design the 85th st interchange this way, but they took maybe the most dangerous intersection I have ever seen and made it maybe twice as dangerous.

I assumed it would be like this: https://en.wikipedia.org/wiki/Magic_Roundabout_(Swindon) or this: https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst... . Instead, topologically, it is a normal roundabout, just with unusual (negative) curvatures.

The linked ones, also called "magic roundabouts", are roundabout rings made out of roundabouts. In particular, you can take them clockwise or anticlockwise - it is a ring of roads connected by mini roundabouts. Even just the road sign gives you a headache!

Having been exposed to the idea for over a decade, I still don't know instinctively how to navigate them.

I'm all for hating bad infrastructure, but this roundabout seems pretty straightforward? Maybe it's different when you're actually driving on it, but from a topdown view it's clear it's a central roundabout with some extra sidelanes to avoid the roundabout if you're immediately turning right.

I used the roundabout the game is modeled after the other day. This is at the freeway exit used to get to the Costco AND downtown in Kirkland. I've seen pileups here for no reason. It's insane.

To be fair, I'm not sure there's a good solution. The real problem is the volume of traffic and that it dumps onto two lane roads at the edges of this roundabout. To really fix things you need to give people other exits to use.

The figure-8 central design makes this roundabout not a real roundabout. The challenge is that the entry and exit points are at the tightest part of the curve, making ingress and egress kind of weird. It looks like they did it because of space constraints on the bridge. What I find weird is the tightness of the on/off ramp, which share a very small part of the central lanes. In a traditional circle, they are spaced more apart, making exiting and entering smoother.

If it were a regular 2-lane traffic circle, it wouldn't be too difficult to navigate.

Personally, I find multiple-lane traffic circles (4+) to be more difficult to navigate, mostly when some people in the center lanes pull a fast right turn across all lanes of traffic. Otherwise, much better than traffic lights at keeping traffic moving or first-come, first-served stop intersections when people don't really stop or sit there waving you through.

I live a couple of blocks away from this Kirkland roundabout and I drive through it very often -- almost every time I go anywhere. Overall, I like it. My average traversal through the roundabout, for just about any source/destination, seems a bit faster than the pre-roundabout infrastructure and much faster than the temporary so-many-stoplights configuration they had for the past year or two.

The top down view seems to make this extra confusing:

1. You don't get to see signage that tells you what lane to be in

2. You are forced to take in irrelevant details.

I drove on this for the first time yesterday, once from 405 S to 85th W, then back on 85th E and 405 N. Super easy, the lanes are fairly nicely signed and there is ample signage. No issues at all.

This is so stressful to play. Can you change the music?

Background music is awesome

I swear if the US could build regular roundabouts, converting an intersection would make the accident rate go down, instead of up.

I love this roundabout, we live down the street from it. People around here drive comically bad, mostly from what i suspect is simple inexperience (many new drivers), with a surprising side of entitlement (super rich area). Together, its become my favorite experience to see all the ways people fail to navigate this wild "roundabout".

And yet it still mostly works, and is loads faster than the former lights that were there before, so i suspect it will be a success in most eyes once everyone adapts.

For additional fun, check out the sticker price on this intersection overhaul (which includes much more than the round about).

Just shared a relevant video for anyone interested: https://news.ycombinator.com/item?id=48565808

Not a joke, actual roundabout.

The new 85th St & I-405 interchange is horrible. I took it twice and both times it's too stressful and takes much longer to get off 405.

Love it, you’ve got to do 132nd street next. Trying to exit south bound during rush hour is delightful

"time for bed" said Zebedee.

I'm a huge roundabout fan, but this does indeed look nasty. Seattle area driving in general is pretty bad. There's an exit on the 5 in downtown Seattle that's on the far left lane (Seneca street I believe) that feels like putting your life on the line every time you need to take it.

Hilariously great

In my town of Shrewsbury PA we have a diverging diamond traffic pattern(it's sorta like a figure 8). I have no issue with it tho I have seen a car accident or two there. Roundabouts are simple and so is the diverging diamond.

The basic failure mode I would expect:

https://www.youtube.com/watch?v=DeFY9u69tkE

The adjoining roads have a large speed differential. The runoff areas around this project do not appear as if designed with this in mind. I predict a few horrible accidents and some hamfisted redesigns.

The local news has a ground level view of this project:

https://www.youtube.com/shorts/jlPMB7c0RyQ

Roundabouts are almost always a bad idea. Thank God they are mostly a European thing.