There were small borders that were placed around the settlement. They weren't quite walls per se, but more like barriers, where there would be gates and a group of vampires that would stay as permanent guards.
This was because for the most part, the settlement was safe. There would rarely be attacks from beasts, and there were next to no attacks from the outside, but just in case, they did need to install safety precautions.
One of these precautions that had been installed were towers. There were several towers that were embedded with crystal energy and technology, and there were guards as well. The idea was that those in the towers could see if an attack was coming from afar, or if one was coming from above.
At the same time, the towers had large amounts of crystal energy that could be used to form a barrier, if there was some sort of attack from the outside or above. All of this was an especially automated system designed mostly by Vincent with the help of a few others.