Rio Tinto Mining Park

The Rio Tinto district has been mined for copper, silver and gold since at least the third millennium BC, worked by Tartessians, Phoenicians, Romans and, from 1873, a British consortium that transformed it with open-cast pits, a railway to the coast and a company town at Bella Vista built in English style with a Presbyterian church and a tennis club. The river running from it is deep red from dissolved iron and extremely acidic, with a pH around two, and the extremophile bacteria living in it have drawn NASA and astrobiology researchers studying analogues for Mars. Visitors can ride a restored mining train along the river, tour the Peña de Hierro pit and an underground gallery, and see the museum and a Victorian house.

What you actually see

• The red river - acidic water coloured by dissolved iron.
• The mining train - restored carriages running twelve kilometres along the valley.
• The Corta Atalaya pit - a vast terraced open-cast excavation.
• Bella Vista - the British company quarter with Victorian houses.

When to go

Spring and autumn; the area is hot and exposed in summer. Train departures are limited and run on set days, so checking the timetable before travelling is essential.

Honest expectations

The train runs to a restricted schedule with few daily departures and sells out. The landscape is industrial and scarred rather than scenic, which is the point but not to everyone's taste. Do not touch the river water, which is strongly acidic.

Nearby

Aracena and its cave lie north; Huelva and the Donana marshes are southwest.