Final answer:
The map of Jamestown Fort shows that it had been totally destroyed more than 130 years ago at the very least.
Step-by-step explanation:
Based on the information provided in the map of Jamestown Fort, it can be concluded that the fort had been completely destroyed at least 130 years ago.
Several key details support this inference. Firstly, the fort appeared abandoned, with damaged buildings and fortifications. This suggests that the fort had undergone significant destruction, likely rendering it uninhabitable. Secondly, the gates of the fort were down, further indicating that it had been breached or fallen into disrepair. Lastly, there were no signs of human presence or activity, such as people or sounds, which implies that the fort had been deserted for an extended period of time.