December 11th, 2020 at 6:01 AM
I love using highways in Cities Skylines. I have the network additions mod, which gives extra highways such as 2-lane, and 4+ lane highways (all the way up to 6). It's immensely helpful for building sprawling highway networks for busy cities.
I enjoy the challenge of funneling as much traffic as possible through an intricate network of interstate routes. I tend to merge several highways into a single superhighway to feed my downtown/CBD areas, and as a result, the majority of the city's traffic tends to depend on one single link. It's absolutely critical, as a result, that it's set up well and is up for the task.
Luckily, there are a few things that can make a HUGE difference for the highway capacity in the game. (And I should add, make sure you have TPME. )
1. Don't use too many lanes. - Learned this one the hard way. CIMs LOVE to get confused if you give them super-wide highways, and they tend to do those ridiculous cross-highway lane jumps that grind the entire highway to a halt. So on this one, less is sometimes more. 4 lanes can actually handle a metric f***ton of traffic. In fact, even the standard three lanes can already handle a ton of traffic on its own, and two lanes is still far more robust than any other non-highway road in the game. So don't rush to add too many lanes too quickly, sometimes you don't need them quite yet.
2. Lane management is your best friend. If you're gonna funnel 200,000+ CIMs into one superhighway, lane management is the single most important thing you can do. It is absolutely critical that every single interchange has very tightly defined rules for which lanes CIMS can marge in and off of. Use TPME to set custom paths, and make sure to touch all of the ramps for your highways.
In fact, I've found that it's actually extremely rare for a highway to actually be running "at capacity." Almost always, a busy highway can technically carry more traffic than it already does, but the traffic management must be absolutely razor sharp. Bad lane management (or the absense of it entirely) is usually the biggest bottleneck-factor here.
3. Merge lanes are good (Network Additions Mod). - The faster CIMs are traveling, the more effectively they are able to merge. Merge/Auxilliary lanes keep CIMs from being forced to merge into a busy highway from a tight ramp, and these can massively improve traffic flows for interchanges on busy sections.
To set these up, temporarily widen the highway by an extra lane after the merge. But make sure to use lane management to FORCE CIMS to ONLY merge into your new merge lane. They should not merge into the main lanes until the merge lane ends, which allows them to reach full speed first! Otherwise, they will jump the gun and merge too early, defeating the purpose of the merge lane.
It's very hard to tell from the above (toaster-PC) screenshot, but this entire city is split into two halves and is connected primarily by a single interstate highway. This superhighway branches off into three other interstates that serve separate districts of the city (and these highways further split into more highways and major roads of their own). So ultimately, 200K CIMs are connected primarily by this link alone.
This link definitely had congestion problems earlier on in the game, but I was able to resolve a lot of its issues by narrowing the highway from 5 to 4 lanes, and by implementing very detailed lane management and merge lanes. That *seems* counterintuitive (the highway has the highest traffic density out of any route in the entire city), but it has worked well and the traffic flows without a hitch! That being said, the city has grown and it's now starting to reach its limits with 200K CIMs and five interstates being funneled into it. (I think it's about time to bring the 5th lane back? )
What are your thoughts on using highways in Cities Skylines? What is the busiest highway/thoroughfare you've ever designed? Do you have any tips for maintaining massively busy interstate networks in your cities?
I enjoy the challenge of funneling as much traffic as possible through an intricate network of interstate routes. I tend to merge several highways into a single superhighway to feed my downtown/CBD areas, and as a result, the majority of the city's traffic tends to depend on one single link. It's absolutely critical, as a result, that it's set up well and is up for the task.
Luckily, there are a few things that can make a HUGE difference for the highway capacity in the game. (And I should add, make sure you have TPME. )
1. Don't use too many lanes. - Learned this one the hard way. CIMs LOVE to get confused if you give them super-wide highways, and they tend to do those ridiculous cross-highway lane jumps that grind the entire highway to a halt. So on this one, less is sometimes more. 4 lanes can actually handle a metric f***ton of traffic. In fact, even the standard three lanes can already handle a ton of traffic on its own, and two lanes is still far more robust than any other non-highway road in the game. So don't rush to add too many lanes too quickly, sometimes you don't need them quite yet.
2. Lane management is your best friend. If you're gonna funnel 200,000+ CIMs into one superhighway, lane management is the single most important thing you can do. It is absolutely critical that every single interchange has very tightly defined rules for which lanes CIMS can marge in and off of. Use TPME to set custom paths, and make sure to touch all of the ramps for your highways.
In fact, I've found that it's actually extremely rare for a highway to actually be running "at capacity." Almost always, a busy highway can technically carry more traffic than it already does, but the traffic management must be absolutely razor sharp. Bad lane management (or the absense of it entirely) is usually the biggest bottleneck-factor here.
3. Merge lanes are good (Network Additions Mod). - The faster CIMs are traveling, the more effectively they are able to merge. Merge/Auxilliary lanes keep CIMs from being forced to merge into a busy highway from a tight ramp, and these can massively improve traffic flows for interchanges on busy sections.
To set these up, temporarily widen the highway by an extra lane after the merge. But make sure to use lane management to FORCE CIMS to ONLY merge into your new merge lane. They should not merge into the main lanes until the merge lane ends, which allows them to reach full speed first! Otherwise, they will jump the gun and merge too early, defeating the purpose of the merge lane.
It's very hard to tell from the above (toaster-PC) screenshot, but this entire city is split into two halves and is connected primarily by a single interstate highway. This superhighway branches off into three other interstates that serve separate districts of the city (and these highways further split into more highways and major roads of their own). So ultimately, 200K CIMs are connected primarily by this link alone.
This link definitely had congestion problems earlier on in the game, but I was able to resolve a lot of its issues by narrowing the highway from 5 to 4 lanes, and by implementing very detailed lane management and merge lanes. That *seems* counterintuitive (the highway has the highest traffic density out of any route in the entire city), but it has worked well and the traffic flows without a hitch! That being said, the city has grown and it's now starting to reach its limits with 200K CIMs and five interstates being funneled into it. (I think it's about time to bring the 5th lane back? )
What are your thoughts on using highways in Cities Skylines? What is the busiest highway/thoroughfare you've ever designed? Do you have any tips for maintaining massively busy interstate networks in your cities?