This very popular painting is often said to be one of the gate of present Firuz Shah Kotla.
Even i was confused thinking it must be a representation of a gate which was tgere once.
It was actually Kushk e Anwar near Mehdian (near present day Maulana Azad Medical College).
It stood between The Turkman and Delhi gates. Now there is no trace of it.
It was within the boundaries of the 5th city of Delhi,Firuzabad but not near or within present day Firuz Shah Kotla.
No one is sure of its purpose
Kushk means palace but it seems useless as a dwelling place.