The Plaza de Armas (Plaza of Arms) is the name for the main square in many Latin American cities. In 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.
Most cities constructed by the Spanish Conquistadores were designed on a standard military fashion based on a grid pattern, taken from the Roman Castrum, of which one of the blocks 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. 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 Plaza Mayor or Plaza de Armas of Lima, is the birthplace of the city of Lima, as well as the core of the city. Located in the Historic Centre of Lima, it is surrounded by the Government Palace, Cathedral of Lima, Archbishop's Palace of Lima, the Municipal Palace, and the Palace of the Union.