At the northwest corner of the Salé medina, where the old sea wall meets the Atlantic, sits a stone platform of cannons looking out over the Bou Regreg river mouth. This is Borj Adoumoue, one of the corner bastions of Salé's 17th-century defensive system, built during the era when Rabat, Salé and the Kasbah des Oudayas together formed the so-called Republic of Salé — a corsair confederation that needed serious gun emplacements to defend the estuary from Spanish and Portuguese raids. The Alaouite sultans later reinforced it with additional batteries.

The bastion today sits on a grassed platform above the beach, with its original 17th- and 18th-century bronze and iron cannons still set into their embrasures and pointing where they always have. There is no museum, no shop and no ticket office — the platform is an open-air heritage spot that locals come to for the sea breeze and the long view. Interpretation panels are limited, so a little pre-reading on the corsair history helps the visit considerably; a small marabout's tomb sits beside the bastion, and behind it the long white expanse of the Salé cemetery rolls inland.

The view alone justifies the climb. From the platform you can see the Kasbah of the Udayas across the water on the Rabat side, the Atlantic opening west beyond the river mouth, and the Salé medina and cemetery on every other side. From Rabat, take the tram across to Salé and walk or short-taxi to the seafront near the old cemetery; alternatively, cross by rowboat ferry and walk up through the medina (about 25 minutes on foot). Late afternoon into sunset is the moment — the sun drops into the Atlantic directly beyond the river mouth, both medinas light up, and the wind can be strong, so a layer helps.