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There are few city-builders out there as expansive asCities: Skylines 2. Complete with everything from wide-ranging maps, in-depth public transportation, and the ability to literally make something from the ground up. As fun as making your own city can be, it’s also a very daunting prospect given all the tools at your disposal.
One of those basic tools you’ll need for creating roadways are tunnels. These subterranean wonders are excellent for connecting your districts, establishing city-wide public transport, and maintaining the natural environment. In this guide, we’ll go over how to build a tunnel and the economics behind it.
How to Build a Tunnel
Your first decision is figuring out what depth you want the tunnel at.A road will be fully underground at -12.5m or below, any higher and the road will be unroofed – a nice design choice for the urban metropolis, but not quite a tunnel.
To create the tunnel, start by entering theroad building tooland select the road type you wish to build with.Place the starting point of your route at ground level,then decrease the elevationto build a descent ramp, this needs to be a reasonable length otherwise the game will consider the route too steep for traffic.
The step button next to the road elevation arrows lets you change height in smaller or larger increments – ranging from 1.25m to 10m.
After you’ve placed a descent ramp, you may continue the tunnel by creating more roads at the same elevation or repeat the previous step to descend even further. Once you’re ready to return to the surface,place a new road starting point at the end of the tunnel - using same elevation, then increase the elevation to 0m, building out a suitable path for your ascent ramp that’s not too steep for traffic.
A tunnel can be built below a ground level road so long as the tunnel is 12.5mbelow it. Tunnels can overlap one another so long as there’sat least 8.75m between each level- meaning your pedestrians can walk above your cars, which can drive above your trains, and so on. The only limit is the maximum depth, which is capped at -50m.
Remember your utility pipes and cables. Whilst you can move these pipelines around your roads, it helps to have a preset elevation for your service infrastructure – if your water and sewage pipes are all 10m underground, then you can guarantee transport routes for everything below that.
How Much Will a Tunnel Cost?
For a two-lane road the base cost is about ₡2 per metre, at -10m that same road now costs about ₡3 per metre. For any depth at 12.5m or below (a fully enclosed tunnel), that same road will cost a whopping₡15-16 per metre.
The good news is the price of a tunnel is fixed, no matter how deep it is built. The bad news is that tunnels increase upkeep costs dramatically. The upkeep of 100m of two-lane road at surface level will cost ₡16 a month, at 10m underground that rises to ₡28 a month, while that same road at a depth of 12.5m or lower will cost a hefty ₡90 a month.
Overall, tunnels are a fantastic way to move the hustle and bustle around your city quickly and efficiently, but unless you’ve got the unlimited money option selected, be careful to balance your underground ventures alongside your budget.
