Mining flourished in the province of Murcia, on the Mediterranean coast in south-eastern Spain, from Roman times. The Carretera del 33 (Way of the 33) is a road that links the community of La Unión with the port of Portmán. From 1869 until the last mines closed in 1991 the principal mineral extracted was pyrites, used in the manufacture of sulphuric acid, but there were also workings for tin ore.
The Parque Minero de la Unión (Mining Park at La Unión) is an open air museum commemorating the mining industry whose principal feature is the mine called the Mina Agrupa Vincenta which is registered as a property of cultural interest. Visitors go first to an interpretation centre where there are multi-media displays on the history of the area. A train them takes them through a landscape full of industrial monuments to the Mina Agrupa Vincenta. Amongst the features of the landscape are a lake of ochre-tinted water, a gunpowder store later used as a chapel, an ore washery of 1820 which used technology, including buddles, from Cornwall, and worked until 1957, lakes where fines were deposited, and a serpentine flue where lead particles were deposited from the smoke as it ascended to an outlet on the hill top. Visitors can gain some understanding of the harsh working conditions endured by generations of coal miners in Murcia, and can learn something of other mines in the vicinity. The museum stages an annual festival of music and flamenco dancing called the Cante de las Minas.