El Telègraf

El Telègraf, also known locally as Torre Fossada, is a stone tower from a 19th-century military optical telegraph line, standing in the municipality of Castellbisbal, in the Baix Llobregat comarca, Barcelona province. Protected as a Bé Cultural d'Interès Nacional (an asset of national cultural interest), the tower rises above a narrow passage of the Llobregat river, close to the crossing known as Pont del Diable. It appeals to visitors curious about pre-electric long-distance communication and about the closing campaigns of the Spanish Civil War in Catalonia.

Where exactly does the tower stand?

The tower sits at the point where the Llobregat river cuts through a gorge near the Pont del Diable, within Castellbisbal's municipal boundary, at roughly 41.4745°N, 1.9418°E. The spot was chosen for its clear sightlines up and down the valley — a practical requirement for any station in an optical signalling chain.

What does the building look like, and why "Fossada"?

The tower is square in plan, roughly 5 metres to a side and about 7 metres tall, with two storeys and a rooftop terrace. Its entrance sits on the upper level, originally reached by a raised platform spanning the moat that surrounds the structure like a miniature fortification. A small window closed by a segmental arch lights the top floor. That surrounding moat, crossed by a drawbridge-style platform, is the source of the tower's other name, Torre Fossada — the "moated tower."

How did it work as part of the telegraph network?

Built in the mid-19th century, the tower belonged to the military optical telegraph line linking Barcelona and Lleida. Within the Baix Llobregat stretch of stations it was numbered tower 4, relaying signals directly to and from the neighbouring towers at Molins de Rei and Esparreguera. Operators displayed coded shapes or signal arms at the top of the tower; the next station read them through a telescope and repeated them onward, letting messages travel the length of the line far faster than a rider on horseback.

What happened here during the Civil War?

Decades after its original telegraph function had faded, the tower found a new role. During the Spanish Civil War, Torre Fossada became the main Republican defensive position guarding this crossing of the Llobregat. The position held until 25 January 1939, when Nationalist forces took Castellbisbal and the defence of this stretch of the river came to an end.

What can visitors see today?

The tower survives as a physical record of two very different chapters — a pre-electric signalling network and a Civil War front line. Its national heritage protection covers both the tower itself and the surrounding moat, allowing the original defensive layout of the structure to still be read on site.

Frequently Asked Questions

What is El Telègraf in Castellbisbal? A 19th-century military optical telegraph tower, also called Torre Fossada, protected as a Bé Cultural d'Interès Nacional.

Where is it located? Above a gorge of the Llobregat river in the municipality of Castellbisbal (Baix Llobregat, Barcelona), near the Pont del Diable crossing.

Why is it also called Torre Fossada? Because of the moat surrounding the tower, originally crossed by a raised drawbridge-style platform — a small-scale fortification feature.

What was its original purpose? It was station number 4 on the Barcelona–Lleida military optical telegraph line, relaying visual signals to the towers of Molins de Rei and Esparreguera. It later served as a Republican defensive position during the Spanish Civil War, held until 25 January 1939.