Aurangzeb built the Shahi Eidgah or place to offer prayers on Eid on outskirts of Shahjahanabad.
Today it’s within the city
I visited it a few days before Eid is Azha or Bakreid
Shahi Eidgah was built on a area of 31,484 sq yds land, surrounded by thousands of sq yds / sq ft open maidan ( grounds ), which were also for the namazi.
The Shahi Eidgah complex has 2,83,257 sq fts, which at any time can be used by 50,000 namazi. The main gate at the front side has also two small gates besides it for the entrance and exit of the devotees. The same pattern is followed on the north and south sides of the Shahi Eidgah.
( from shahi eidgah’s official website)