An unused rail line will be rusted but a line in use will be polished from the wheels of trains. Also, an unused line will usually be overgrown with weeds etc Well, other than the above, you really can't tell. I have known several lines with weeds and other things on the track, and are still used for light freight. Try to (legally) find the closest signal light and see if its active (lit any color). Be very careful. You could also ask your local council, or at the nearest railway station etc. The best option is to assume that any tracks are live. If railroad tracks exist, you are probably tresspassing in the first place. If the tracks are covered in rust, they may not be used that often, but rust won't protect you from a run-away car travelling at 60 mph. Out of a railroad yard possibly 30 to 60 miles away.
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Darien Short Line Railroad ended in 1894.
I'm not sure...
Parallel lines.
There is a long-gone rail system in South Florida that connected the towns of Jupiter and Lake Worth. The stops were called Mars, Jupiter, Juno, etc. which gave it its name. Most of the stops have been abandoned and the land was redeveloped, but we still have the towns of Jupiter and Juno Beach.
That would be the 'Short Line' railroad.
Technically no. They're property of whichever railroad you stole them from. If the line is abandoned, they still don't belong to you, and depending on how the scrap yard is run they may accuse you of theft.
It could vary from a few miles to hundreds of miles. The definition "short line" is just a short-cut description of privately owned sections of track that (usually) branch off of a main line (Class A) railroad. It may supply transport for a single factory, join two factories, or be the remnant of an abandoned main line RR.
Bay Line Railroad was created in 1994.
Soo Line Railroad was created in 1961.
There are several abandoned railroads in Tennessee. One of them is the CSX industrial branch which is located in Oak Ridge, TN.
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Hi-Line Railroad Bridge was created in 1908.
Philadelphia Belt Line Railroad was created in 1889.
Hokuriku Railroad Ishikawa Line was created in 1915.
Seaboard Air Line Railroad ended in 1967.
Seaboard Air Line Railroad was created in 1900.