Herrenknecht AG is a German

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 manufacturer of tunnel boring machine

Tunnel boring machine

A tunnel boring machine also known as a "mole", is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They can bore through anything from hard rock to sand. Tunnel diameters can range from a metre to almost 16 metres to date...

s of all sizes. Herrenknecht is headquartered in Allmannsweier near Schwanau

Schwanau

Schwanau is a town in the district of Ortenau in Baden-Württemberg in Germany. It was formed in 1971/1972 with the merger of the villages of Allmannsweier, Nonnenweier, Ottenheim and Wittenweier.-External links:* *...

 and is the world market leader for heavy tunnel boring machines. Roughly two-thirds of the 1850 employees work at the company headquarters and roughly 300 work at three different locations in China

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

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As of 2005, Herrenknecht holds the world record for constructing the largest tunnel boring machines in the world, at 19 metres (62 ft) diameter.