The Ensanche of Madrid: How the City Grew from Medieval to Modern

Until the mid-19th century, Madrid was essentially a medieval city in its layout: dense, narrow, without modern sanitation, unable to absorb the growth of an expanding centralised state. The Ensanche changed that. It is the urban plan that created modern Madrid — and it defines entire neighbourhoods that today's residents inhabit without knowing they were designed in a drawing office in 1857.

The city before the Ensanche

In the mid-19th century, Madrid had around 300,000 inhabitants concentrated within the medieval walls and in unplanned peripheral neighbourhoods. The city was unhealthy: unpaved streets, no sewerage, contaminated water. The cholera epidemics of 1834 and 1855 killed thousands of people.

Madrid's fiscal wall — built in 1625 and extended to 1785 — had been demolished in 1868, but its line still defined the limits of the built city. To the north and east, open fields awaited development.

The Plan Castro (1857)

In 1857, military engineer Carlos María de Castro presented the government with the Ensanche de Madrid project. The plan established the ordered expansion of the city in three sectors:

• North: Chamberí (middle bourgeoisie, grid street layout)
• East: Salamanca (upper bourgeoisie, the Marquis of Salamanca as developer)
• South: Arganzuela (working classes, industry)

Castro's plan envisaged blocks of 100 × 100 metres with chamfered corners, wide streets of 20–30 metres, interior gardens within the blocks, and the separation of uses (residential, industrial, public facilities).

The Marquis of Salamanca and the neighbourhood bearing his name

José de Salamanca, Marquis of Salamanca, was the great developer of the eastern extension. He bought land in the eastern sector in the 1860s and built the neighbourhood that bears his name today: wide streets, bourgeois buildings, private mansions. The Salamanca neighbourhood was, from its origins, the district of the aristocracy and the haute bourgeoisie.

Chamberí: the middle-class city

The northern extension — Chamberí — developed at a more organic pace, without a single major developer. It became the neighbourhood of the Madrid middle class: merchants, civil servants, professionals. Its grid layout and 19th and early 20th-century rental apartment buildings define the Chamberí we see today.

The 20th century: from Ensanche to metropolis

Castro's Ensanche was gradually completed through the late 19th and early 20th centuries. In the first half of the 20th century, Madrid grew beyond the original Ensanche with new neighbourhoods such as Cuatro Caminos, Almagro, and Retiro, and later with the large post-war peripheral developments.

Today, the Ensanche — Salamanca, Chamberí, Almagro — remains the most valued residential heart of Madrid, with the city's highest property prices.

See also our guide to 18th-century Bourbon Madrid and the Salamanca neighbourhood.

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References:

• Castro, Carlos María de — Memoria descriptiva del anteproyecto de Ensanche de Madrid. Madrid, 1857.
• Sambricio, Carlos — Madrid, vivienda y urbanismo, 1900-1960. Akal, 2004.