Quattro Canti was laid out on the orders of the Viceroys between 1608-1620 by Giulio Lasso and Mariano Smiriglio at the crossing of the two principal streets in Palermo, the Via Maqueda and the Corso Vittorio Emanuele.
The piazza is octagonal, four sides being the streets; the remaining four sides are Baroque buildings, the near-identical facades of which contain fountains with statues of the four seasons, the four Spanish kings of Sicily, and of the patronesses of Palermo, (Christina, Ninfa, Olivia and Agata). The facades onto the interchange are curved, and rise to four floors; the fountains rise to the height of the second floor, the third and fourth floors contain the statues in niches. At the time the piazza was built, it was one of the first major examples of town planning in Europe.
References:The Chapel of St. Martin is the only completely preserved Romanesque building in Vyšehrad and one of the oldest in Prague. In was built around 1100 in the eastern part of the fortified outer ward. Between 1100 and 1300, the Rotrunda was surrounded by a cemetery. The building survived the Hussite Wars and was used as the municipal prison of the Town of the Vyšehrad Hill.
During the Thirty Years’ War, it was used as gunpowder storage, from 1700 to 1750, it was renovated and reconsecrated. In 1784, the chapel was closed passed to the military management which kept using it as a warehouseand a cannon-amunition manufacturing facility. In 1841, it was meant to be demolished to give way to the construction of a new road through Vyšehrad. Eventually, only the original western entrance was walled up and replaced with a new one in the sountren side. The dilapidating Rotunda subsequently served as a shelter for the poor.