Ultimate 3-way junction
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README.md
Railway Junctions
Junction Criteria
3-Way junctions
Basic 3-Way
Line Merge
Half Cloverleaf
Half Spaghetti
Compact 3-Way
Compact 3-Way B-M Junction
Ultimate 3-way
Half Transmogrified
Braided Junction
4-Way junctions
Basic 4-Way
Roundabout
Cloverleaf
Spaghetti
Star
Complex Star
Branch-Merge
Tetrathorp
High Speed 4-Way Fly-over∕under
Pre-Signaled Roundabout
Advanced Roundabout
Right-of-way Roundabout
Improved Roundabout
Transmogrified
Tightlong
Deepblue2k8 4-way Junction
Enormous junctions
Multi-way/multi-track cloverleaves
Dual Tetrathorp
Dual Transmogrified
Dual Branch-Merge
Quad Branch-Merge
Quad Tetrathorp
6-tuple Branch-Merge
8-Way Star
High Speed 4-way
Other junctions
Building depots
Dual tunnels
Sideline U Turn
Right-of-way Lane Change
Priority Merge
Track Layouts
4-Way Triple Axial
4-Way Triple Axial 2
Triple Via Mini
High Hill
Unuseful junctions
Crossover
3/4ths junction
Ultimate 3-way junction for 4 tracks

Similar to the Half Transmogrified junction, but with tunnels instead of bridges and some tracks connect at different points.

Ultimate 3-way junction

Junction Criteria
CostAverage
Construction DifficultyModerate
TunnelsYes
BridgesNo
Breakdowns
Broken down trains affect one line.
Sharpest Turn3
HillsYes
Split Before MergeYes
Direct PathsYes
Natural TurnsYes
DeadlockNo
LoopsNo
Signal type Any

Pros
  • High speed.
  • High traffic capacity.
  • Jams very unlikely.
  • Small area.
  • No sharp turns, can be easily built for any train length.
  • Adequate waiting space for turning trains.
Cons
  • Signaling gaps from tunnels. (doubling tunnels makes junction at least 2x2 tiles larger and harder to build)
Tips
  • Start by building the "short diagonal" track first. Make its length equal to your longest train.

Variations

Here's a slightly different mainline example:

3-way over-under

Junction Criteria
CostAverage
Construction DifficultyHard
TunnelsYes
BridgesYes
Breakdowns
Broken down trains affect one line.
Sharpest Turn4
HillsNo
Split Before MergeYes
Direct PathsYes
Natural TurnsYes
DeadlockNo
LoopsNo
Signal type Any

Pros
  • High traffic capacity.
Cons
  • Slow, unless tracks are diagonal.
  • Jams more likely than in ultimate 3-way junction.
  • Requires space between tracks.
  • Sharp turns, unless tracks are diagonal.
  • Not enough waiting space for turning trains.
  • Signaling gaps from bridges and tunnels.
  • Bridges slow down high-speed maglev trains.