The Plaza Mayor, also known as the Plaza de Armas, is the main public square in Lima, Peru. It's been around since 1535 when Francisco Pizarro founded the city. Surrounded by important landmarks like the Government Palace and the Metropolitan Cathedral, this square has seen it all - from markets to bullfighting rings to historic proclamations of independence. It's basically the heart of Lima, where history and modern life collide in a bustling urban space.