The Royal Geographical Society Picture Library has a photograph showing Railway & telegraph plant for Kandahar / Defence tower & barracks for troops / Railway terminus at Charman, taken by AC Yate in 1896.
The preview is a bit too small to see very much, but it might show the railway stores which were allegedly in place ready for rapid construction of a line across the border from British India to Kandahar in the event that Imperial Russia made a move on Herat.
There is also a view of the Railway station at Chaman: tug of war – Pathan v Punjabi Mohammedan (2nd) Baluchis in Pakistan, also by AC Yate and dated 1896-97.
Presumably the photographer is the Captain AC Yate who wrote The Transcaspian Railway and the Power of the Russians to Occupy Herat in 1891, arguing for building a railway to Sistan (the Afghanistan/Iran/Pakistan border area), rather than Kandahar: The press and the public are at this moment advocating the extension of our railways to Kandahar; but that this could be done without precipitating a rupture of our relations with the Amir is doubtful
.
The RGS has various other interesting photos – a search for railway
brings up shots of colonial (and other) lines, and there are views of the Bolan Pass line.