A very simple Interchange

So here is a common occurence: You have a road crossing your highway:

We can quickly turn this into an interchange by adding an on- and offramp on one side

...and then repeat the same thing on the other one

There you go, you have a working interchange.

Now while this works reasonably well in low traffic, a common problem is, that a car might have to go this way:

Doing this it has to cross two intersection, blocking all the other exits and entrances. This can quickly lead to a lot of congestion.

Let's look into an actual 3-way then:

The 3-Way Prefab

Luckily enough the game already has a prefab for a 3-way interchange. The only problem with it is that you can't do this (in 99% of all cases that is):

So first we have to bulldoze a lot of road to be able to build it (you should pause your game when doing stuff like this or you will likely cause traffic and also electricity problems)

Next we can build it and reconnect everything

And that is already all there is to it. This simple interchange should be enough for pretty much all you 3-way intersections, if you do get traffic problems you can propably identify a root cause somewhere else

The 4-Way Prefab

Now for cases where we actually need to cross our highway:

We can use the 4-way cloverleaf prefab in the same vein:

Again, this is already very efficient and should be enough for most of you needs

Next, let's go into understanding, what we actually just built