Numantia (Spanish: Numancia) is an ancient Celtiberian settlement, whose remains are located on a hill known as Cerro de la Muela in the current municipality of Garray (Soria), Spain.

After twenty years of hostilities, in 133 BC the Roman Senate gave Scipio Aemilianus Africanus the task of destroying Numantia.

Numantia was an Iron Age hill fort (in Roman terminology an oppidum), which controlled a crossing of the river Duero.

The Arevaci were a Celtiberian tribe, formed by the mingling of Iberians and migrating Celts in the 6th century BC, who inhabited an area near Numantia and Uxama.

Scipio Aemilianus in command of an army of 30,000 soldiers laid siege to the city, erecting a 9 km barrier supported by towers, moats, impaling rods, and other devices.

In 1999, the Roman camps were included in a zona arqueológica, a category of the Spanish heritage register which did not exist when the hillfort was first protected.

More recently, Carlos Fuentes wrote a short story about the event, "The Two Numantias", in his collection The Orange Tree.

To erase the memory of the Republican president Manuel Azaña, they renamed it Numancia de la Sagra.