Refugi 307

Excavated by hand by Poble-sec neighborhood residents between 1937 and 1938 to protect civilians from systematic fascist aerial bombings.

Encompasses 400 meters of subterranean tunnels with electrical wiring, municipal water taps, ventilation shafts, an infirmary, and 90-degree blast-deflection turns.

Over 1,400 neighborhood shelters were excavated across Barcelona during the war, creating one of Europe's most extensive civilian defense networks.