I saw something interesting yesterday. They did not want Yerushalayim to not be special like shushan, so they made it that a walled city is considered walled for the megilla as long as it had a wall during Yehoshua Bin Nun’s times. During the story of Purim it did not have a wall
As a matter of fact , even shushan did not have a wall by Yehoshua Bin Nun’s times.
Sam2 is correct – Tiveria, sefas, chevron all lain twice. On shushan purim without a bracha