On 16 June 2010 Asian Development Bank approved a further USD700 000 from its Technical Assistance Special Fund for:
A study on railway development for Afghanistan completed for the following routes: (i) From Hairatan at the border with Uzbekistan to Heart [Herat] in the west, via Mazar-e-Sharif; (ii) from Shirkhan Bendar at the border with Tajikistan, via Kunduz to Naibabad [which is on the line under construction from Hayratan] joining Mazar-e-Sharif to Heart; (iii) from Torkham at the border with Pakistan to Jalalabad; and (iv) Spainboldak at the border with Pakistan to Kandahar.
Source: Railway Development Study (Supplementary) : Afghani., Is Rep. of, 2010-06-16
Taking it literally, this seems to miss out the link needed from Chaman in Pakistan over the border to Spin Boldak in Afghanistan.