The top photo, taken from the fort’s gun deck, shows the view south from the rear of the sentry box. From the fort’s website:
“The sentry box or garita had fallen off sometime during the 1800s while Fort Matanzas sat abandoned. It was rebuilt of brick in 1927 and again of coquina in 1929 using steel reinforcing rods to attach it to the existing parapet walls.”
The lower photo was also taken from the gun deck of the fort, looking south toward Matanzas Inlet. It shows how the fort’s battery commanded the river and inlet, which was about one-half mile closer in the 18th century.