The physical expansion of the city also began in the 1860s. The Habsburg emperor Maximilian ordered the construction of the Avenida del Imperio (now Paseo de la Reforma), a wide boulevard that joined the city centre with the imperial residence at the Castillo de Chapultepec (now housing the Museo Nacional de Historia). The 18th century base of the residence was designed by the Catalonian Agustín Mascaró (1786) with a refashioning in 1864-1865 by Ramon Rodríguez Arango ity with the assistance Eleuterio Méndez. The tower was amplified in 1878 by Angel Anguiano who was both an architect and an astronomer. Maximilian brought in other European and Mexican architects including Hofmann. Castillo de Chapultepec was used as the official presidential...