At least one train in the AM pulls west to about MP53 (about a mile west of High Bridge) to layover while another train comes up behind them and heads east out of High Bridge. Its stick rail and the track is in good condition. Haven't made it out to MP54 yet.......almost once, but didn't work out
From ARCH interlocking to MP54 is considered a "station track" and revenue trains are allowed to use up to MP54. From MP54 to MP60.1 I think it is, NJT owns and maintains, but is considered OOS. West of MP60.1 is owned by NS as I believe it is the Central Running Track.
At ARCH, you have the main through the station, which is the track closest to the station building. the other track is im assuming the former leg of a wye and connection to the High Bridge Branch. Just before where it would have turned to go north, there is a bumping block. you can see where the track was cut in the woods.
That track comes back into the single track at ARCH, and at the other end of ARCH, a passing siding starts on the South Side of the Single. That track is the passing siding, and continues through Annadale Station (the track closest to hte parking lot, that the stupid little asphalt walkways are over, is the siding) and continues to CLINTON interlocking, which is right under the Route 22 and I78 bridges, by the Annandale exit (16 i think?).
From there, its single track to the new siding, called the Whitehouse Passing Siding which splits off the Single at Cush, and comes back in at Tunk (going east). After that, its single track to Brad, and at Brad (west end of Raritan Yard), it looks like double track, but its not, as the track inbetween Brad and Boyd (east end of Raritan yard) is the Raritan Running track, and is used for laying over/storing of trains and equipment. the "offical" double track starts at Boyd, where the single track turns into Track 1, and the Raritan Runner runs into Track 2. Its double track all the way to Aldene.