I saw one parked, of all places, on the northeast corridor. This one was only for continuous tie replacement. The rails were splayed outward while the machine pulled and replaced ties. It's Longer than the station's platforms! I wonder how long it takes to get into motion in the morning.....
The one I saw was in the process of starting on a new section. It was a long time ago, so I don't remember exactly how long it took, but it was long enough that we almost gave up. We had traveled hundreds of miles to watch trains going over the loop, only to find that the track was out of service!
Later that day we drove past a yard where all the trains were holding up, ready to go once the track replacement was done: there were at least six trains with all their engines idling: it was quite a sight!
Indeed. Went that way once and expected a train or two while there. Nope. Best I recall now there were six. Almost as though they were chasing each other at slow speed. It's only *slightly* more scenic than the horseshoe curve. (Which I should revisit, to expand the trip to Allegheny portage)
The portage predates the railroad over the mountains... And only small relics remain. But as for 1820s engineering, it was a marvel!