The Bala Hissar, or "High Fort", of Kabul was for many centuries the seat of a ruler and played an essential part in state development in Afghanistan. Fortifiedfrom perhaps the 6th Century', the fortress reached its peak under Mughal rulers in the 16th and 17th Centuries. Its palace was rebuilt by an Afghan king in the late 18th Century and British troops were stationed in the fort during each of the 19th Century Anglo-Afghan wars. After 1880, the upper Bala Hissar was used as an arsenal and prison; the lower part became a ruin, within which new military installations were later built. The site was extensively damaged during fighting in the 1990s but it remains in military use.
This paper examines what can be learnt about the former structure of the Bala Hissar, particularly in the early 19th century, when it was still a great fortress palace, and then identifies changes that were made later in that century.
Source: Bill Woodburn
Woodburn, Bill. The Bala Hissar in Kabul: Revealing a Fortress-Palace in Afghanistan (pp. 1-42). In The Institution of Royal Engineers Professional Paper No. 1, Kent: 2009.