Version 1.2 is a release file of the Minecraft resource pack IR DarkRaider's Monorails [Immersive Railroading Pack], made for Minecraft 1.12.1, 1.12, 1.12.2. It was published on May 27, 2019 and is 3.8 MB in size. For the full description, screenshots and every other version, visit the IR DarkRaider's Monorails [Immersive Railroading Pack] resource pack page.
How to install: Put the .zip into .minecraft/resourcepacks (do not extract it) and enable it under Options → Resource Packs.