The Unión Explosivos Río Tinto (ERT) was a Spanish business conglomerate that operated between 1970 and 1989, being present in many industries of the country.

At the time, it was the main Spanish business group by size and assets, with a network of companies that included more than forty subsidiaries.

In its beginnings, it had a workforce made up of 14,000 employees,[2] as well as a network of facilities, factories and production centers that extended throughout the country.

During the 1970s, the Explosivos Río Tinto group undertook a business diversification that led to an increase of its presence in the real estate, pharmaceutical, petrochemical or publishing sectors.

In 1989, after many years of crisis due to financial problems, ERT was integrated into the holding Ercros.