Deepblue2k8 4-way Junction
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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

An easy 4-way junction named after Deepblue2k8, a user on the tt-forums who posted it there: [1]

A straight forward basic 4 way junction.

Pros

Cons

Improvement

Using both bridges and tunnels, we can reduce the number of hills for the trains, so that each train has at most one up-hill.

Modification of the juction to reduce the number of hills, using both bridges and tunnels.