Pedra do Leão

A wide arch driven straight through a single emergent rock is the whole reason to make the short zodiac crossing to Pedra do Leão. Drop onto the rock and head for the passage, where schools of fish typically hold station, parting around divers as they swim through instead of scattering. The passage itself sits at about 5-6 metres; smaller boulders draped in algae ring the main rock. Past the arch, a band of brown algae roughly 20-30 metres wide runs out to a flat sand bottom at the site's 14-metre maximum, where an undulate ray turns up occasionally. Average depth across the dive sits around 8 metres, between the shallow arch and the deeper sand. It's a short, simple dive built around one strong moment rather than a long route: enter, work the arch, extend onto the sand if air and time allow, then head back.

Pedra do Leão takes its name from the lion-like silhouette of the rock itself, which most catalogue write-ups mention before they get to the diving. What makes the site more than a landmark is the passage cut clean through it: divers swim the length of it with fish holding station inside, parting around them rather than scattering. That kind of clean swim-through is not something every Sesimbra rock offers; a wall or a boulder field is the more usual shape here, and only a couple of neighbouring formations come close. Combined with a shallow 14 m ceiling, it makes for one of the more approachable named boat dives in the cluster, next to deeper draws like the River Gurara wreck (20-33 m, advanced-only).

The fish-filled arch is the shot: both independent catalogue write-ups for this site single out the passage's schooling fish as the clearest photo opportunity here, with the animals parting and regrouping as divers move through instead of bolting. A wide-angle setup suits the passage itself; work from outside the arch first to let the schools settle before pushing through. Suggested gear across the two listings varies (some name a hood, gloves and boots for the cooler water, others just a camera and a dive flag or SMB), so bring standard cold-water kit alongside whatever housing you're using.

Dive Club Cipreia, based in Sesimbra, runs trips to Pedra do Leão. The site is boat-only, reached in 10-30 minutes by zodiac from Sesimbra's harbour; there's no shore option. The swim-through is described as wide and easy by the operators who dive it, but one source separately reports a current can run through the constriction, so check conditions with your guide and let them lead the first pass. The site sits inside the Professor Luiz Saldanha Marine Park, a zoned park and not a single no-take reserve; no diver-facing fee or permit was found here, so an operator's trip price is the only cost. Visibility on this stretch of coast typically runs 10-20 m, sometimes dropping to 5-15 m, and tends to be clearest against the grain of the season: January-February over the summer peak. Water sits around 14°C in winter and up to about 20°C in summer, so a dry suit is the standard winter choice with a semi-dry suit covering summer.