I've never seen track geometry like this..

[learmoia]

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Credit to Train Of Thought as the source of the photo.

I don't think they are double slip switches..

It seems to be switches built on top of each other to avoid two yard ladders.

Interesting..

~Ian

[Chris333]

I think those are called lapped turnouts?

[nkalanaga]

I've heard them called (very rarely!) lapped, or just lap, turnouts.  They weren't common in most situations, but could be found in very cramped areas.  Docks definitely qualify.

As you probably noticed, there is no way to go straight through on either of those tracks.