ON-I:

Oranje Nassau Mine 1: 1899 - 1974.
Production: 31.978.000 ton.
Location of mine site: Heerlen.
Number of shafts: originally, 2, later (1905 - 1912) a third was constructed.

The mine site next to the Heerlen railway station is now the location of the main office of the Dutch Governmental Statistics Service, "Centraal Bureau voor de Statistiek, or CBS. Of the mine only the former main office building of Oranje Nassau Mines, and shaft buildings of shaft 2 survive. The Oranje Nassau-I mine was the oldest, but second largest of the ON-mines, and at the mine site also several washing plants, and an elctric powerplant were situated. Especially the powerplant, and the two high chimneys, locally called "Lange Jan" and "Lange Lies", (i.e. Tall John and Tall Lizzy), and the enormous cooling towers determined the skyline of Heerlen for many years.