What is the famous fort of Bahawalpur?

What is the famous fort of Bahawalpur?

بہاولپور کا مشہور قلعہ کون سا ہے؟
Explanation

Derawar Fort is located in the Cholistan Desert, Ahmadpur East Tehsil, Bahawalpur.

The height of the walls of Derawar Fort is 40 meters

The fort was built in the 9th century by Rai Jajja Bhatti, a Rajput ruler.

The Nawabs of Bahawalpur took control of the fort in 1733