Gualeguaychú is a city in eastern Argentina, close to the border with Uruguay. It’s known for its annual Carnival celebrations held in the Corsódromo, a converted former railway station. The city lies on the west bank of Gualeguaychú River, with several beaches. It’s also home to 2 thermal baths. Across the river is the expansive, leafy Unzué Park, with a lagoon, trails, playgrounds and picnic sites.