Arnedo is the third largest town in La Rioja, Spain.

In pre-Roman times it was known as Sadacia or Sidacia, while the current name derives from the Latin Arenetum ("Place of sand"); the Romans, who arrived here in the 2nd century BC replacing the Celtiberians, built here a fortification to defend the hill, which commanded an important communication hub.

The Moors conquered Arnedo in the 8th century AD and made it the capital of one of the 26 provinces in which they divided Iberia.

The town was conquered by the Christian king Sancho I of Pamplona in 908-909.

On 5 January, 1932, there was a clash between the Guardia Civil and a group of striking workers.