The ground under Barcelona, age by age

The plain before the city#

The French army occupied Barcelona from 1823 to 1827. In those years its military engineers measured the zone outside the walls where building was forbidden: 2,088 hectares, from Montjuïc to the edge of Gràcia and to where El Clot and Poblenou begin. The map has 54 sheets and a contour line every metre.

What you see here are their hand-coloured sheets, laid on the relief they drew. The city inside the walls is a blank on the map: they did not survey it.

Lanes of 1827 with a street on their line#

Under today’s city, in gold: the 1827 lanes with at least 70% of their length within 15 metres of a street today running the same way. That is 49.2 km of 262.4. For comparison, the same rule on the map shifted by 60 metres in eight directions finds only 4.3–7.0%: that is the level of the control maps, shifted over a city full of streets.

Street by street#

Some streets pass the test one by one as well: Travessera de Gràcia (942 m), Carrer de Pere IV (1,067 m), Carretera de la Bordeta (692 m), Carrer de la Creu dels Molers (580 m). On Passeig de Gràcia, both of the boulevard’s side roads follow the line of the 1827 lane: 955 and 779 metres, against an average below 80 metres for the control maps.

The streams under the streets#

The 1827 map also draws the water: streams running down from Collserola to the sea, the rieres, and irrigation channels. In blue, the named ones. Rambla de Catalunya has 1,786 m within 15 metres of the stream the map calls the Riera de Mallol; the same line shifted by 60 metres catches 556 m on average and at most 1,599 m.

Carrer de Casp passes the test along the Riera de Malla (615 m), Carrer de Milà i Fontanals along the Torrent dels Caputxins (786 m), and Carrer d’en Fontrodona along the Torrent de la Font Trobada (1,063 m). The streets follow the line of the stream beds of 1827.

The edge of the walls#

The hole in the middle has the shape of the fortified city: the bastions, ditches and glacis show as steps in the relief. The star to the east is the Ciutadella, the fortress built after the siege of 1714; its ground was given to the city in 1869 and is a park today.

Towards the sea, the 1827 shoreline runs well behind today’s quays: 333 hectares of today’s land, in the port and on the beaches, were water on this map.

Barcino, in the middle of the blank#

In the blank of the French map lies the oldest city. The Roman colony of Barcino first had a wall about 1,200 metres long, enclosing about 10.3 hectares; later a second, much thicker wall with 76 towers was built against its outer face. The line on the map follows the course of the wall; its height is only suggested.

On Mont Tàber, 16.9 m high today, four 9-metre columns of the Roman temple still stand, in Carrer del Paradís. Carrer del Bisbe and Carrer de la Ciutat, Llibreteria and Call keep close to the line of the colony’s two main streets.

Under the streets, in 1938#

The 1946 aerial photo is the closest view in time of the whole city to the city of the war years. The orange dots are the 1,242 air-raid shelters in the city’s archaeological map. On the city’s list, 1,270 of the 1,323 are galleries dug like a mine, and 1,171 were begun in 1938, when the city was being bombed from the air.

Half of today’s postal addresses have a mapped shelter within 114 metres. In Ciutat Vella, half are within 61 metres of one; in Sarrià-Sant Gervasi, within 260 metres. One of the raids, on Plaça de Sant Felip Neri on 30 January 1938, has its own page on this site.