I used to call these signal towers as a kid. You find them near railyards where operators can flip levers and change signals down the track for engineers to follow.
With the very limited space I have on my Small Door Layout I needed something narrow and tall. Keeping this to just 8 studs wide allows me to slip it between any two parallel rails. I kept the detail to a minimum but the part count is still 950.
Here's a link to a good article about one of these towers that was replicated. https://heritagerail.org/2015/08/monticello-replicates-an-interlocking-tower/
Here's a link to a good wiki page. https://en.m.wikipedia.org/wiki/Interlocking
I'll upload the .XML file to my Bricksafe page soon. Hope you like!