The town of Kastro has a great set of narrow steep streets. Kastro is an open museum with 4000 years of history. The exterior walls of the medieval houses adjoined and formed the defensive wall with only exits and entries through five vaulted porches. Typical features of the settlement are the closeness and the lack of communal spaces and courtyards, which along with the need for defence led to the construction of houses with two and three floors. Small houses of one room and narrow façade are built in the exterior ring, while big mansions in the interior.