Alcácer do Sal sits at the heart of one of Portugal's great rice-growing regions, and that fact shapes almost everything you eat here. The local arroz de lingueirão — a soupy, intensely savory rice made with razor clams pulled fresh from the Sado estuary — is the dish that defines the town. Order it at a riverside tasca and you'll understand immediately why regulars drive considerable distances just to sit down to a bowl. The rice has a particular creaminess here that you simply don't find elsewhere.

Beyond rice, the estuary delivers an embarrassment of riches to local tables. Eels, sea bass, and fat mullet are grilled over charcoal or slowly braised with olive oil and garlic in ways that feel ancient and unhurried. The covered market near the old town is worth a morning visit — vendors sell hand-dug clams, salt from the nearby pans, and rough country bread that pairs beautifully with the region's soft, rindless sheep's cheese. Pick up a wedge and eat it on the castle steps without apology.

For a proper sit-down meal, locals gravitate toward a handful of unpretentious family-run restaurants along the waterfront and tucked into side streets near the old Moorish quarter. Portions are generous, wine is poured freely, and no one will rush you. Finish with a sericaia — a fragrant, cinnamon-dusted egg pudding that's the dessert signature of the Alentejo — ideally accompanied by a glass of local Moscatel. It's the kind of ending to a meal that makes you immediately want to book another night.