The Chaj Doab lies between the Chenab and the Jhelum and holds Gujrat, Sargodha, Mandi Bahauddin and Jhelum district's lowlands. Its central bar was the Kirana Bar.
The Lower Jhelum Colony was cut into it from 1901 with Sargodha as its centre, and it carried the horse-breeding grants.
Chillianwala and Gujrat, the two battles that ended the Sikh state in 1849, were fought in this doab.
The Kirana hills, a low outcrop near Sargodha, are among the oldest exposed rock in the subcontinent and are geologically unrelated to anything else in the plain.
The Chaj Doab is entirely in Pakistan.
The Chaj is the driest of the three doabs of central Punjab and its bar country, the Kirana Bar, carried pastoralists until the canals arrived in 1901. The change from grazing to irrigated wheat took about a generation.
Bhera on the Jhelum side is one of the oldest surviving walled towns in Punjab, with a Hindu and Sikh commercial quarter that emptied in 1947 and a great deal of pre-modern building fabric left standing precisely because nothing replaced it.
The doab's horse-breeding grants, tied to the Lower Jhelum Colony allotments, produced remounts for the Indian Army for forty years. What happened to that stock and that expertise after 1947 has not been written about on either side.