Cap Negret and the River Algar: Altea's volcanic shore

North of Altea's promenade, Cap Negret changes the material of the shore. Dark volcanic rock interrupts the pale pebble beaches, while the nearby River Algar brings permanent fresh water to a protected wetland mouth. Together they make a compact walk through geology, ecology and twentieth-century coastal history.

Why it matters

The ofite outcrop is interpreted as the neck of a submarine volcanic episode around 220 million years ago, during the tectonic break-up of Pangaea. Quarrying later removed part of the rock. A surviving 1937 machine-gun bunker belongs to a chain planned against a possible landing during the Civil War. At the Algar, year-round flow supports riparian plants and makes the river an ecological corridor toward Serra Gelada.

Plan the visit

Approach Cap Negret from the public shore and look for colour, crystal texture and the relationship between dark rock and fossil beach without collecting samples. Continue toward the Algar mouth on available promenade and beach sections. Pebbles roll underfoot, river levels change after rain and the outcrop is not a scramble route.

• Wear shoes for loose pebbles and wet rock rather than smooth sandals.
• Leave volcanic stones, fossils and plants exactly where they are.
• Give nesting or feeding birds space at the river mouth.
• Check sea and river conditions after storms before attempting the shoreline link.

Connect the story

The Altea old-town guide supplies the white hill settlement usually seen in photographs; this route explains the darker natural foundations of its bay.

Sources

Written in September 2026 from Altea council's Cap Negret Natural Monument guide and the Generalitat's Serra Gelada places-of-interest record.

Shore access, river flow and conservation measures vary. Respect the natural-monument boundary and current coastal warnings.