Peu de Negre

Peu de Negre sits at the base of El Negre, a 1.5 km submarine ridge that runs parallel to the Mataró coastline and is widely considered the most important diving structure on the Maresme coast. The ridge itself is built from porous biogenic rock — a formation compared to tropical coral barriers — riddled with holes, overhangs, and crevices that shelter an unusually dense concentration of reef life. You navigate along the ridge face, following its contours as the rock texture shifts between smooth biogenic surfaces and rough, encrusted walls. Morays and conger eels share the crevices with spiny lobsters and the larger European lobsters (bogavantes) that distinguish this section of the ridge.

Nudibranch diversity is the headline here. The section of El Negre closest to Mataró — where Peu de Negre sits — is noted for a variety of species that sets it apart from the other Maresme ridges, where the fauna tends toward larger, more mobile animals. The biogenic rock creates a micro-habitat of surfaces and textures that supports dense invertebrate colonisation, making the site a natural draw for macro photographers. AcuSub documented the dive with 4K video in 2019, describing the experience as "magnífica" — a verdict shaped by the rock's biological richness rather than any single large-animal encounter.

Water conditions at El Negre can run green and cold, particularly outside summer — plankton-rich water that feeds the invertebrate life but limits visibility. A torch is essential for inspecting crevices where morays and lobsters retreat during daylight. The ridge is long enough that multiple dive points exist along its 1.5 km length; Peu de Negre is one section, not the whole formation. Ask your dive centre which section of El Negre suits conditions on the day — wind direction and current can make some sections more accessible than others. Both Blaumar and Niman Sub operate from Port de Mataró and know the ridge's sections well.