Serra do Risco is one of continental Europe's tallest coastal limestone cliffs, dropping nearly 382 m vertically into the Atlantic. The 11 km loop traces its crest on the sea side — continuous ocean views — and returns inland past the Marmitas do Gigante: circular karstic cavities, a geological feature unique in the park.
It's a hard trail. Not officially waymarked — most Arrábida trails aren't, and this one in particular demands a GPS track. Between kilometres 6 and 8 the ground turns technical: very rocky, dense scrub. Cliff exposure is real; don't try it in strong wind, and don't approach the edge without mountain experience.
With that said, it's the most memorable walk in the Arrábida. The silence is total — only the sea, 400 m below. Boots, long trousers, long sleeves (for the heather), two litres of water per person. Skip it in high summer (open heat, no shade) and in wet winter (slick rock). Autumn is the right window.
Last reviewed: 2026-04