Spanish Civil War 1936–1939
Iron Belt trail, Zamudio (Berreaga–Gaztelumendi ridge)
Trenches & fortifications
The story
Zamudio lies directly below the stretch of the Iron Belt where the Nationalists broke through. The fighting of 11–13 June 1937 spread along the Berreaga–Urrusti–Gaztelumendi ridge, and on 12 June the attackers crossed the line and came down into Zamudio. A signposted 11.1 km memory trail, marked with support from Gogora (the Basque Institute for Memory, Coexistence and Human Rights), climbs to the ridge past surviving trenches and machine-gun nests. It is one of the best places to understand what the Iron Belt actually looked like on the ground, and why it failed against massed artillery and aircraft.
What you can see today
Original trenches and concrete machine-gun posts along the ridge, with explanatory panels and waymarks.
Plan your visit
Start from the panel at the Arroeta car park in Zamudio. The 11 km loop takes about 4 h and is hilly; wear walking boots.
- Parking
- Arroeta car park, with the route's information panel
- Access
- 11.1 km signposted route up to the Berreaga–Urrusti–Gaztelumendi ridge and back
Checked September 2026 from official sources: euskadi.eus. Things change, so check before you travel.
Sources
- geonames.org/search.html?q=Zamudio&country=ES
- euskadi.eus/gobierno-vasco/-/noticia/2020/puesta-en-valor-y-senalizacion-del-itinerario-del-cinturon-de-hierro-en-zamudio/
- uribe.eu/discover/iron-belt
Nearby sites
- Artxanda – Iron Belt trenches & memorial · 4 km
- Gaztelumendi breach – Larrabetzu Iron Belt bunker · 7 km
- Monte Sollube battlefield · 13 km
- Iron Belt Interpretation Centre, Berango · 13 km
- Casa de Juntas & Tree of Gernika · 16 km
- Pasealekua air-raid shelter, Gernika · 16 km
All 158 sites in Spanish Civil War 1936–1939 →
The Spanish Civil War 1936–1939
A free field guide for your phone: the route, the maps and the stories built in, even with no signal. The battlefields, trenches, ruined villages, shelters, museums and memorials of the Spanish Civil War across the whole of Spain, told fairly from both sides.
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