Qila Rai Pithora also known as Fort of Prithviraj Chauhan from where the emperor Prithviraj Chauhan ruled. Before that Prithviraj Chauhan was the king of Ajmer. Later, the kingdom of Delhi was given to King Prithviraj Chauhan by his maternal grandfather.
Some references -
1. https://collections.vam.ac.uk/item/O108056/colonnade-of-hindoo-pillars-at-photograph-bourne-samuel/
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