Stack
A high-speed stack interchange, different from my previous 5-level one because of its reduced height and more sweeping curves. I’d say this is very much an ‘I-20 near Dallas, TX’[en.wikipedia.org]-type of interchange; they seem to grow on trees there!
Size: 228×228 cells laterally (including some shallow splits and merges at the ends), 40 cells across the diagonal when measuring the right-hand connectors, and about 54 cells across when measuring the left-hand ones.
Base cost: 124880 (phwoar!)
Upkeep: 1474 p/w
Max height: 27 meters
Right-hand drive
Built with:
Precision Engineering
NoPillars
Fine Road Heights Mod
Usable without mods!
Part of my real life-sized interchange collection.
Check out the guide I created on making these kinds of real life-sized interchanges.
Compared to my earlier, five-level effort, this four-level stack is both lower and larger in footprint. The former because it lacks a ground-level frontage road system of course, and the latter because the left-hand connectors are designed for a slightly higher speed.
Still, the interchange clocks in at a 27m maximum height, showing that a reduced horizontal footprint (compared to say, a turbine) comes at the cost of increased vertical size.
As for its design speed: the semi-direct flyovers have got 16×16 cell @ 45° minimum curve radiuses, meaning that they can be taken at about 75 km/h. The right-hand connectors are slightly slower at 13 cells @ 45° meeting at their shorter ends (around 65 km/h), but at least I was able to transition them into 18 cell @ 45° de- and accelerating curves – about the normal Highway Ramp speed of 80 km/h.
Aggressive superelevation (banking the curves) would probably work splendidly to make the right-hand turns a bit faster, but unfortunately this option is not available to us in Cities: Skylines.
As for its general layout, this stack interchange is very much inspired by the 1970s cookie-cutter designs done in Dallas’ I-20[www.texasfreeway.com]. Quite different from the five-level mania that started to take over Texas about a decade later!