Pedra do Meio

Pedra do Meio sits a short boat ride from the exit of Sesimbra's harbour, built around two large flagstones running west to east. Follow the flagstones out and back and the navigation is done; the crevices and holes cut through the rock carry the interest. This is where local divers watch cephalopods at the very start of their lives: octopus, cuttlefish and squid lay eggs among the cracks, and hatchlings turn up if you know where to look. Conger eels and moray hold in the deeper gaps, and one report also notes triggerfish, wrasse and the odd scorpionfish on the same ground. Depth tops out around 13-14 metres, an easy single-tank dive that rarely pushes bottom time.

The draw here is timing: divers who slow down at the crevices catch octopus, cuttlefish and squid actually laying eggs, then can return weeks later for hatchlings working their way out. That sequence, visible up close and repeatable through the season, is why underwater photographers keep coming back with macro lenses, drawn by the cephalopod breeding activity in the reef's cracks. The shallow profile and simple two-flagstone layout put beginners in the same spot as the photographers, since no advanced buoyancy or navigation is needed to hold still at a crevice and watch.

The site sits inside the Professor Luiz Saldanha Marine Park; organised groups need park authorisation, typically arranged through the dive operator. Boats use the harbour's exit channel directly overhead, so stay close to your group on the ascent and surface together, not scattered. One report notes Atlantic swell and surge can build here; time your entry and exit to the conditions. Old fishing gear occasionally snags on the reef, so keep kit trim and carry a cutting tool. Water runs cold in winter, so plan a drysuit outside the summer months.