The Paseo de la Reforma reoriented the expansion of the city from the colonial center to an area more easily open to development for residences and businesses of the capital's middle and upper classes, separating them from the poorer and indigenous residents of the colonial core. Development occurred especially during the President Díaz's regime (1876-1911). Structures were of more modern and diverse architectural design. Few of these original houses built in different European architectural styles remain and office blocks have been built on their place over the years. Although there is no single block that has kept its former architecture, a couple of scattered buildings show the opulence enjoyed by the elites during Porfirio Díaz' regime.