Why are the buildings in Barcelona so unified?

When it comes to the urban planning of Barcelona, it is inevitable to start with Ildefons Cerdà. Born in 18 15, Catalan civil engineer, urban planner and social activist died in 1876, which laid the foundation for the impressive octagonal lattice urban texture that often appears in Barcelona city videos and various tourist souvenirs. Ildefons Cerdà was born into a wealthy family in a small town near Barcelona. 184 1 After graduation, the engineer has been committed to the municipal engineering construction of Spanish cities such as Barcelona, including the planning of streets, water supply and drainage, and remote communication networks. Since his father and brother died and Zelda inherited property, he began to be an active political activist and worked hard to realize his ideal city. His famous Barcelona urban planning, the so-called "Plan Cerdà", was implemented in 1859, but it was actually designed as early as 1854. 1854 In Barcelona, the second largest city in Spain, the rapid population growth has overwhelmed the narrow streets and backward urban health system of this ancient city formed in the Middle Ages. On the other hand, since the Middle Ages, Barcelona is not only an important trade city of Spain, but also the capital of Catalonia with independent culture and developed economy. In this place where Catalan rather than Spanish is the first language, the sense of cultural autonomy is particularly strong. Since the18th century, the Bourbon dynasty abolished Catalonia's autonomy and even banned Catalan as the official language. Catalan culture has been severely suppressed, and the people and the government hope to gain confidence and hope for development through urban construction. The wall of the old city was demolished in this year, and the expansion and renewal of the city is imperative.