The more determined railway fans from South Asia would appreciate this weighty book by Simon Darvill (2013):
It gives most details of industrial locomotives which ran in the countries between Afghanistan and Myanmar. A special feature is the lengthy section on the British Army’s military railways in what is now India and Pakistan, including the large amount of rolling stock and other material sent to other theaters of WW1 and WW2.
An interesting point (which one had not come across earlier) is that there was a serious plan to lay a 2’0″ Decauville track across the Khyber Pass from the then railhead at Jamrud, crossing the border and extending into Dakka Fort in Afghanistan during the 3rd Afghan War in 1919. This was some years before the “real” broad gauge line was built to Landi Kotal and Landi Khana.
However, there is no direct mention of this little line in accounts of the war. So there is some doubt if it was actually built. It would have probably been a little over 50 km long. Mr Darvill has found evidence that some equipment had been dispatched to the region. Details are on p.493.
While the stress is on steam, there are plenty of diesel locomotives listed as well. Profusely illustrated with b/w photographs.
This book may be available from amazon com and amazon in. Otherwise it is available from specialized bookshops in the UK. Sellers can be located by using Google for the book’s title or ISBN no 9781901 556827
International shipping charges will be high as the packed weight is over 1.5 Kg.
Footnote: Dakka is too obscure to be found on Google Maps, but you can take its location at 34.2222 N, 71.0347 E. It is on the road from Torkham to Jalalabad.