Remember, this is still a 2D project. The second dimension is up! Instead of XZ axes, it's XY.
There are still multi layer travel options available. And some previously unthinkable possibilities (e.g. moving walkways like the kind you see in airports, for short distances within a block – or different colored trains on different levels like ground/underground) are still possible.
There are still multi layer travel options available. And some previously unthinkable possibilities (e.g. moving walkways like the kind you see in airports, for short distances within a block – or different colored trains on different levels like ground/underground) are still possible.