Algeciras is not a gastronomic destination, but it eats well for a working port city. The area around Plaza Alta and the streets of the old town have the most authentic options — tapas bars where the clientele is entirely local, where a beer comes with a free tapa automatically, and where the fish is fresh from the bay and the strait.
El Copo — near the port, one of the best seafood restaurants in the city, reliable for local fish including red mullet, sole, and the excellent seafood of the Bay of Gibraltar. The grilled fish is simpler and better than any elaborate preparation.
Bar El Generoso — a classic tapas bar in the old town, known for its fried fish and the automatic tapas that come with each drink. Order the boquerones (anchovies) and the tortilla.