Enter dimtrain minecraft:the_nether and you will get a list of all trains in the nether, and you should also see that some trains are missing a graph.Example:Train {"text":"Unnamed Train"}, index 54 is missing a graph. Train {"text":"Split off from: Unnamed Train"}, index 89 is...
You'll also want it near important resources, such as at the mouth of your main mineshaft, near your farms, or close to your Nether Portal. Scour your map for a good place to construct your new castle. You may want to build near a village so that you can act as their lord. ...