This fort is the closest one to the town. It’s the easiest one to visit as no boat is needed. However, the other one is the first line of defense and is three levels and more interesting. (You can get to the other one by renting a kayak and enjoying the harbor as well.
Today, the cannons lie on the ground. In their day, they rode atop wheeled wooden carts so they could be pulled in, loaded from the front, then wheeled out to be shot. A small hole is at the top so the fuse can be lit.