This is a splitting viaduct section built to be wall mounted. This goes with the brackets and other components my printed viaduct system.
The support brackets for this are located here:
https://www.printables.com/model/312249-n-scale-model-train-viaduct-bracket
https://www.printables.com/social/261772-alex-mackinnon/collections/336869
This section accommodates 4 mainline tracks with Kato's track system and allows for offramps from the viaduct. In the photos, this is at the back corner, and was used where the quad tracked section splits in to two pairs. I've also provided the sketchup files which have the overall arrangement of this part of my setup.
Print upright. This was designed to be made on a tall printer with no supports.
The author hasn't provided the model origin yet.