Railroad Track
Train Track, Railway Track, Track, Line
noun
A line that runs on a road is a railroad track. First you have to get into your mind that the "line" in question is a railway line. Then, what railway line runs on a road and what kind of road is it? It's a railroad track.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
線路には、何があっても入らないで下さい。
Never go on the railroad tracks, no matter what.
家の前に線路があるので、電車の音が大きいです。
There is a train track in front of the house, so the noise from the train is loud.
兄は必ず線路が見えるよう、電車の後ろの車両に乗ります。
My older brother always gets on the last car of the train so that he can see the train tracks.