@Green Fox: I totally agree. Since the implementation of adding props, trees and decorative networks with IMT this has become a possibility. I'll look into this!

The interchanges in this collection along with those in your anno 2021 service interchanges have become some of the ones i use most frequently. They generally have lane connections (in TM:PE) and node placement done in a very thoughtful manner that makes the traffic flow well for a given interchange layout. Lane and intersection markings are saved in IMT, so things look good when these are placed. Many of these intersections are quite large, so they can be a bit challenging to place if you haven't reserved a lot of space for them.
The main general improvement that I might suggest would be to improve the lighting at the actual intersection points. At night, the area surrounding the intersection nodes is often the darkest area of the whole interchange, which may be due to limitations of the underlying road assets you use.

Ah, very cool! Thanks for all the info.

@TheBloke: The amount of on- and off-ramps is determined by the designs as they are used in real life. I've based them on standardised interchange designs as illustrated on Wikipedia. Link: https://de.wikipedia.org/wiki/Autobahnkreuz
And: https://de.wikipedia.org/wiki/Anschlussstelle_(Autobahn)

Thanks very much! I never bothered with IMT before, thinking that I didn't really care about anything that was purely aesthetic and didn't affect the simulation. But now I've started, I actually quite enjoy having all the roads looking right :)

Since yesterday I decided to upgrade the service roads on the Parclo to 3 lanes; here's what I came up with: https://i.imgur.com/p00g8l8.jpg

This is probably quite unnecessary, I just tend to stick large roads in everywhere. Was the reason for the one-off/two-on design because that's the max that the roundabout can support anyway? Do I risk bogging it down by allowing more lanes to enter? I suppose with only one lane coming off (which is what I still have as well), there's not really much benefit to extra incoming lanes? Maybe I'll experiment with three-on/two-off as well.

Thanks again for the junctions - having some decently designed road layouts is galvanising me to expand my city.

@TheBloke: You did that perfectly!! They're exactly right!

OK I realised I didn't have the right lane connections at all. And I also decided to battle with IMT to figure out how you added the markings :) Which I managed to do in the end. So I *think* this is correctly converted from your layout to RHD? https://i.imgur.com/ZABs7PY.jpg

Thanks so much for testing that so quickly, Max. That makes sense. In the case of the Parclo A2B I think it's the asymmetrical roads that cause the issue - because they don't get inverted.

It didn't take me long to - I think - fix the Parclo A2B. If you have a moment, could you tell me if this looks correct [i.imgur.com]? I haven't changed the IMT config, just swapped the asymmetrical roads and adjusted the lane connections. I think it's right now, unless I'm misunderstanding something!

Looks like chevrons are facing the wrong way too when LHD is enabled on RHD interchanges...

@TheBloke, I've done some additional testing. As the direction of traffic gets switched around on roads when LHD is enabled, the roads themselves do not. I could've known this!

So it seems only the interchanges that are completely symmetrical can be used with LHD enabled. Some look symmetrical, but even the use of a two-lane road vs a one-lane road can have an impact. Looks like I'll need to make additional interchanges specifically created for LHD.

Most System Interchanges are symmetrical, so these should give no problems. For the other ones I really need to make LHD versions of them. If there are any of them you'd like, let me know!

@TheBloke: Thanks for the feedback. To be honest I haven't tested the interchanges with LHD enabled.

I assumed (perhaps wrongfully) that when you select LHD, the roads would be reversed in such a way that you get the exact same result as RHD. The lanes as I see them in your pic aren't correct. There should be two lanes heading into the roundabout, and one going out. So it's no surprise you got confused by them!

I haven't had this issue/feedback before and I've recently added TM:PE lane connections to the interchanges. Hope this isn't the cause of the issue, otherwise I might've messed some of them up. (well, for LHD enabled games that is...)

I need to have a closer look at this...

Thanks so much for the fast reply, @MaxFX, and the great explanation. I will definitely be experimenting with many of the interchanges, and will study the differences.

I've already added a couple, and hit a small problem.

Am I correct in thinking that some of the modded A2021 interchanges assume LHD traffic?

I added the SRI from the other pack and that looks fine. But then I added the A2021 Parclo AB2, and got confused by the lane arrows, and TMPE lane connectors: https://i.imgur.com/N1WSmkL.jpg

As a test I started a new map, set to RHD, and the intersection made a lot more sense then - it should be two lanes on, one lane off the roundabout, not the other way around?

That's no problem, I'll just re-do the lane connectors. I just wanted to check that I'm correct about that, and whether I should expect this for all roundabout-based interchanges using asymmetrical roads?

Thanks again and sorry for all the questions!

@TheBloke: 1/2 Thanks for your interest! The interchanges from both the 'A2021' collections and the 'Interchanges with Lane Mathematics' are relevant. Main difference is that the interchanges from the A2021 collection are modded, more realistic and therefore a lot bigger in size. But they all perform well within the game.

Now for the amount of traffic they can handle: When it comes to 'free flow system interchanges', these all handle the same amount of traffic and shouldn't create any traffic jams or holdups because there are no conflict points (junctions/roundabouts) present. But these type of interchanges are for connecting two highways with each other.

@TheBloke: 2/2 When it comes to 'Service interchanges' the amount of traffic handled differs quite a bit depending on the interchange! Rule of thumb is that the more on- and off-ramps an interchange has, the more efficient it is. So a Parclo A2 for example has 2 on-, and 2 off-ramps. They are quite efficient, but not as efficient as the Parclo 6-Ramps. And then there are more innovative interchanges like the DDI, SPUI and the Milwaukee interchanges. If you install a good 'Timed Traffic Light' (instructions on their respective Workshop pages) on these interchanges the amount of traffic they can handle is huge!!

Considering their very small filesizes ('intersection assets' are nothing more than blueprints) you could subscribe to all of them (total filesize for the A2021 interchanges is around 13MB). Start a test game with the 'Unlimited Money', and 'Unlock All' mods enabled, and try them out!!

Ps; A turbine for the A2021 series is in the works

One more question: at the same time as subbing to your two A2021 collections, I also subbed to "Interchanges with lane mathematics". I'm unsure whether I should be looking in both collections when adding interchanges, or if you intend A2021 to supersede the earlier "lane maths" collection?

My guess is that they're both still relevant? Eg lane maths contains the SRI an improved turbine design, and I don't see a turbine/SRI in A2021.

Thanks again.

These collections are seriously impressive. Thank you! I'm a bit overwhelmed with all the options and which ones I should use :) In your description you mention that a key difference is how much space they leave around them for building other things. Can I therefore assume that I can choose an intersection based primarily on that, and don't need to think too much about how much traffic each one can take? They will all handle large volumes of traffic? Thanks again.

And possibly a trademark :)

@asterisk11231: The definition of the word 'anno' is: 'In the year'.

So the (full) name of this collection is: 'Cities Skylines System Interchanges in the year 2021'.

The collection has got nothing to do with the Anno games. Just a coincidence it's from the same publisher...

Why the name associated with the Anno series by the same publisher who does Anno / Endless / Humankind?