# Natural and archaeological landmarks in Spain

> Live situation record from CLSTR: https://clstr.news/situations/natural-and-archaeological-landmarks-in-spain
> Updated: 2026-09-17T06:10:34.000Z. Sources: 4. Developments: 2.

The Coves de Sant Josep in Castellón, Spain, is noted for containing Europe’s longest navigable underground river, spanning 2,750 meters. The site offers guided tours that include an 800-meter boat ride and a 250-meter walk through waters maintained at a constant 20°C.

Beyond its geological features like stalactites and stalagmites, the caves possess significant archaeological value. The site contains prehistoric paintings and engravings from the Upper Paleolithic period, approximately 17,000 years ago, and shows evidence of later use by Iberian and Roman cultures. It is recognized as a UNESCO World Heritage site and previously served as a refuge during the Spanish Civil War.

Other natural landmarks in Spain, such as the Cañón del Río Lobos in Castilla y León, also feature significant geological formations, including limestone canyons and protected habitats for wildlife like griffon vultures.

## Timeline

### 2026-09-17: Natural landmarks in Spain feature canyons and underground rivers

Spain hosts remarkable natural sites, including the limestone canyon of Río Lobos in Castilla y León and the Coves de Sant Josep, which features a long navigable underground river.

2 sources. https://clstr.news/cluster/natural-landmarks-in-spain-feature-canyons-and-underground-rivers

### 2026-08-21: Coves de Sant Josep hosts Europe’s longest navigable underground river

The Coves de Sant Josep in Castellón, Spain, hosts Europe’s longest navigable underground river, featuring a 1,050-meter tour and UNESCO-recognized prehistoric art.

2 sources. https://clstr.news/cluster/coves-de-sant-josep-hosts-europes-longest-navigable-underground-river

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Cite as: Natural and archaeological landmarks in Spain. CLSTR, https://clstr.news/situations/natural-and-archaeological-landmarks-in-spain