Which preposition to use with fustat

in Occurrences 1%

The troops deserted Fustat in a panic, and the women of the city, running out of their houses, implored the sherif to intercede with the conqueror.

on Occurrences 1%

He was encamped on the sandy waste which stretched northeast of Fustat on the road to Heliopolis, and there, at a distance of about a mile from the river, he marked out the boundaries of the new capital.

Which preposition to use with  fustat