A couple of weeks ago I visited Minat al-Qal'a, the remains of an Umayyad fort that was repurposed by the Crusaders, on a beach in Ashdod.
Although the site is fenced in, the fence is broken and unfortunately it looks like kids go in there to drink or otherwise party. It doesn't appear that the Israel Antiquities Authority has placed a high priority on this fort, which is very impressive.
Here's my 360 degree panorama from the center of the fort. It renders a little weirdly so I am including the full panorama.
It is large, and includes three mostly identical rooms still enclosed.