The Plaza de Armas (literally Weapons Square, but better translated as Parade Square or parade ground) is a common name given to public squares in Latin America, Spain and the Philippines. There are also examples of squares with that name in North America. In the central region of Mexico this space is known as El Zócalo and in Central America as Parque Central (Central Park). While some large cities have both a Plaza de Armas and a Plaza Mayor, in most cities those are two names for the same place.[1][2]
Most cities constructed by the Spanish conquistadores were designed in a standard military fashion, based on a grid pattern[3] taken from the Roman castrum, of which one block would be left vacant to form the Plaza de Armas. It is often surrounded by governmental buildings, churches, and other structures of cultural or political significance.[4][5] The name derives from the fact that this would be a refuge in case of an attack upon the city, from which arms would be supplied to the defenders.
The Romans elevated the plaza to a place of political power (the forum) within the city. Spain inherited the Roman concept of the city, and by the time of the Renaissance, her powerful kings were ready to build a new Spain, an empire across the ocean, whose engine would be a system of cities and towns. At the microscale, these cities would be anchored by the spacial nucleus, the central place of power - the Plaza Mayor.
King Philip II of Spain, in his Royal Ordinances passed on the colonialists in 1573, decreed that the central public square, or Plaza de Armas, would serve as the fulcrum of colonial town life, and the main nexus for important public and religious buildings.