Most people come to Portimão for the beaches and grilled sardines. This month, though, a lucky few will get a look at something far older: Gruta da Companheira, a cave where Neanderthals are believed to have lived more than 45,000 years ago.
The Portimão Museum is running two guided open days, on October 17 and 24, both starting at 10am. Each visit is capped at 20 people and you have to register in advance — by October 14 for the first date and October 21 for the second, via online forms linked from the museum. Everyone meets in the car park of the Companheira wastewater treatment plant, which sounds unglamorous until you hear why: that's exactly where the cave was found.
Back in early 2016, construction crews building the town's new wastewater treatment plant broke into an unknown underground cavity. It turned out to be only the second cave in the whole Algarve with archaeological material linked to Neanderthal communities. The cave itself is small — two horizontal chambers joined by passages, roughly ten metres in total — and it remains closed to the public. Visitors will instead be shown the excavation area around it, where University of Algarve researchers are actively working.
And the work is paying off. Digs near the cave's original entrance have gone down more than four metres and opened up a new network of galleries containing both archaeological and palaeontological remains. Among the finds: stone tools attributed to Neanderthals, plus bones from deer, horses, turtles and aurochs — the extinct wild cattle that once roamed the region. The research now continues under the Finisterra project, a European Research Council-funded study led by João Cascalheira that looks at how the last Neanderthals in western Europe moved around and developed culturally, with Portimão Council lending logistical support.
The site's deposits date to the Middle Palaeolithic, more than 45,000 years ago, and while findings are still preliminary they're reshaping what we know about who lived in the Algarve and when. For travellers, it's a rare chance to stand at a working prehistoric dig with the researchers themselves — an experience you can't buy later, since these are one-off dates.
Wear comfortable clothes and sturdy shoes; you'll be walking around an active excavation area. If the dates don't work, the Portimão Museum itself is worth a visit year-round, and the town makes a good base for exploring the western Algarve beyond the usual resort strip.
Story first reported by Portugal Resident.
