Castrelos Park, set around the 17th-century Quiñones de León mansion, is the most beautiful public park in Vigo and one of the best in Galicia. The grounds include formal French gardens, a woodland area, and a small lake, all well maintained and open for free. The park has a particular lushness thanks to the Atlantic climate — hydrangeas, camellias, and rhododendrons bloom in season, and the stone walls are draped in moss.
The mansion itself houses the Municipal Museum, which contains a good archaeology collection from the Celtic castro above the city, a room on the Peninsular War, and a dedicated Galician art gallery. Allow at least an afternoon here — the park alone is worth the tram or taxi ride from the centre.