No Sign until the Burst of Fire: Understanding the Pakistan-Afghanistan Frontier, by Thomas H. Johnson and M. Chris Mason. International Security, Vol. 32, No. 4 (Spring 2008), pp. 41–77. (PDF)

According to Pakistani officials, two “established” border crossings handle the bulk of legal daily cross-border traffic: Torkham, in the north at the end of the Khyber Pass, and Chaman in the south. Both are manned by officials of the Pakistani customs service and the Federal Investigative Agency as well as by Levies.4 Another twenty “frequented” border-crossing routes are manned by customs officials, Khassadars, and Levies.5 There are also 111 “unfrequented” (illegal and known) and unmanned crossings in the north and 229 such crossing areas in the south.6 Unaccounted for in this typology of border crossings are hundreds of foot and goat paths used by smugglers, locals, and nomads (i.e., Brahui and Afghan Kuchis), who seasonally cross the border with their herds.8 The vast majority of these crossings are uncharted and are not monitored by either Islamabad or Kabul.
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