The castle was built by Serafín Villarán over two decades without formal architectural training.
The structure incorporates materials sourced directly from the surrounding landscape, including local river stone.
It was designed as a 'living' work, with modifications and additions made continuously throughout the building process.
The castle includes intricate interior corridors that simulate the experience of a natural cavern.
Unlike traditional fortifications, this structure was built as a private passion project rather than a defensive military site.
Castillo de Cebolleros, also known as Castillo de las Cuevas, is a unique hand-built structure constructed entirely by a single resident, Serafín Villarán. Located in the Merindad de Cuesta Urria in Burgos, the edifice is crafted from local stone, gravel, and reinforced concrete. Construction began in 1978 and continued until the creator's death in 1998, resulting in a distinct architectural style that mimics medieval fortress aesthetics. The interior features complex layouts with tunnels, staircases, and various chambers that evoke a subterranean, cave-like environment. It remains one of the most prominent examples of outsider architecture in Northern Spain. The site is situated within the small village of Cebolleros, overlooking the surrounding valley of the Nela River. It is maintained and protected by the creator's family, who oversee visitor access.
The main exterior facade from the village road, which captures the contrast between the castle's rugged masonry and the rural backdrop.
Wear sturdy, closed-toe shoes as the floors are uneven and the interior includes steep, narrow stairways.
The interior pathways are low and tight, which may be challenging for individuals with mobility issues or claustrophobia.
Check with local residents or the municipal office in the village for current access availability before arrival.
Do not attempt to visit without confirming availability, as access is managed by the owner's family and can be restricted.
Access is periodically restricted; always confirm current availability with local tourism boards in the Merindad de Cuesta Urria before visiting.
Respect the site as a private family legacy; do not climb on non-designated structural walls or touch the exterior mortar.
