Editing Construction

Build your subway network by placing blueprint tracks and then building those tracks. Construction costs are calculated dynamically based on multiple interacting factors like elevation, track type, [[train type]], and placement.

== Construction Elements ==

=== Tracks ===

Tracks form the basic infrastructure of the transit network. Players can construct:

* '''Standard tracks''' - Basic directional line segments connecting stations
* '''Parallel tracks''' - Bidirectional pairs typically spaced 3.81 meters apart
* '''Quad track''' - Four parallel tracks where tracks 1 & 2 run in one direction and tracks 3 & 4 run in the opposite direction.
* '''[[Scissors crossovers]]''' - Special track junctions allowing trains to switch between parallel tracks

Crossovers have a fixed cost while standard and parallel track costs can vary based on elevation.

==== Construction techniques ====
Parallel tracks are configured for right-hand running, this is important when laying out bi-directional loops as you will need to select the station platforms on the correct track for the trains to operate.

When laying single-track it is important to note that the track will be laid assuming the same direction of travel that you are laying, so to join two dual-track segments with single track, you will need to lay one track in one direction and the other track in the opposite direction. This also means that you cannot create a single track spur line with the expectation that a single train can shuttle back and forth: it can only go in the direction the single track was laid.

Joining two dual-track lines into quad-track will require connecting one line directly to the inner tracks of the quad-track and one line, using single-track segments, to the outer tracks.

=== Stations === 
Different types of stations allow for single-direction, bi-direction, or express stopping patterns.

* '''Single track''' stations have only one platform and are useful for single-directional loop or a terminus station.
* '''Parallel track''' stations have two platforms and are the typical station used if there are no special requirements.
* '''Quad track''' stations have four platforms and, unlike the other stations are not speed limited to 47Km/h. They are designed to allow an express stopping pattern where local services stop and long-distance services continue through the station at full speed without stopping.

Note that the cost of a '''Quad track''' station is more that the cost of a '''Parallel track''' station with two single track lines built on either side of the two platforms. Careful engineering can therefore save around 27% of the construction cost of each station on a quadruplicated line.

== Track Elevations ==

Elevation is the most significant factor in construction costs, with multipliers ranging from 0.3× to 4.5× the baseline cut-and-cover cost.

{| class="wikitable"
! Elevation Type !! Relative Cost !! Elevation Range (meters) !! Can Intersect Roads !! Requires Building Destruction
|-
| Deep Bore Tunnel || 4.5× || Below −24 m || style="background-color:#c8e6c9; text-align:center;" | ✓ || style="background-color:#fff9c4; text-align:center;" | Depends on building foundation depth
|-
| Standard Tunnel || 2.0× || −24 m to −11 m || style="background-color:#c8e6c9; text-align:center;" | ✓ || style="background-color:#fff9c4; text-align:center;" | Depends on building foundation depth
|-
| Cut-and-Cover || 1.0× || −10 m to −5 m || style="background-color:#c8e6c9; text-align:center;" | ✓ || style="background-color:#c8e6c9; text-align:center;" | ✓
|-
| At-Grade || 0.3× || −4 m to 4 m || style="background-color:#ffcdd2; text-align:center;" | ✗ || style="background-color:#c8e6c9; text-align:center;" | ✓
|-
| Elevated || 0.8× || Above 5 m || style="background-color:#c8e6c9; text-align:center;" | ✓ || style="background-color:#c8e6c9; text-align:center;" | ✓
|}

=== Intersections===
Tracks can intersect at-grade if they are at the same elevation (within 0.1 meters). If the tracks are crossing at different elevations, there needs to be at least 4 meters of clearance between them.

=== Strategy ===

'''At-grade''' construction (0.3×) offers the lowest cost but cannot intersect roads, making it viable only in dedicated rights-of-way or areas without road crossings. Building your tracks around existing right-of-ways to reduce the need for elevated/underground rail and building demolition is the cheapest way to expand.

== Cost Calculation ==

=== Base Formula ===

Construction costs are calculated using this formula:

<pre>
Final Cost = Base Cost × Elevation Multiplier × Configuration Multiplier
</pre>

=== Track Configuration Multipliers ===

The number of parallel tracks affects tunnel and construction width:

{| class="wikitable"
! Configuration !! Multiplier !! Use Case
|-
| Single Track || 0.75× || Terminus tracks, yards, emergency crossovers
|-
| Double Track || 1.0× (baseline) || Standard bidirectional operation
|-
| Quad Track || 1.5× || Express/local service, high-capacity corridors
|}

=== Station Cost Calculation ===

Stations use the same elevation and configuration multipliers as tracks but start from higher base costs ($75M for heavy metro, $50M for light metro).