In 1825, when industrialization was just beginning in Germany and the first railroad was running through England, a company was founded in Siegen that today can look back on two centuries of eventful history: Gontermann-Peipers.
200 years later, this company is not only an integral part of the local economy, but also known worldwide as one of the leading manufacturers of high-performance cast components.
What began with modest means in the Sieghütte district of Siegen has now developed into an internationally successful family business in its seventh generation. “Our passion for metal has made us one of the world's leading foundries,” says managing director and shareholder Frieder Spannagel.
GP is deeply rooted in the local industrial heritage – and, like no other company, stands for the continuation of the Siegerland metal tradition: more than 2,000 years ago, the largest iron smelting furnaces in Central Europe were already smoking here. Today, the two GP plants in Hain and Marienborn near Siegen produce cast components for mechanical engineering, rolls for the steel and aluminum industries, and containers for transport storage of nuclear material.
Over 500 employees
With over 500 dedicated employees, GP is one of the largest employers in Siegen. The anniversary celebrations focus on the people who work at GP and whose relatives have often been with the company for several generations. Gontermann-Peipers has therefore decided to celebrate the anniversary together with its employees and their families as a family festival.
On Saturday, June 21, 2025, the event took place in bright sunshine at the completely renovated Irle Brewery, located next door to the GP plant in Marienborn. Around 1,000 people made up the “GP extended family,” - employees, their families, and long-standing friends and neighbors of GP. The location brought back memories of old times, when every Siegerland ironworks had its own cooling brewery close by.
Social Commitment of the GP Foundation
To mark its anniversary, the Gontermann-Peipers Foundation will donate €20,000 to a number of charitable causes – a token of gratitude for 200 successful years on a regional and international scale.
The DRK Children's Hospital in Siegen will receive €10,000. This hospital plays an important role in providing medical care for children and young people in the greater Siegen area. Another €10,000 will go to Sea Shepherd, an international non-profit direct-action movement dedicated to protecting the ocean and global maritime wildlife.
What has always distinguished Gontermann-Peipers is its ability to think in terms of generations rather than quarters. This has guided the company through turbulent times – from the beginnings of industry through world wars and economic crises to today's challenges such as high energy costs changing steel markets and global trade relations.
“These 200 years are a remarkable piece of history that we all share as a team. We look back with pride and forward with determination,” Frieder Spannagel continues.
So in Siegen, the industrial heart of iron is still beating strongly in 2025 – and Gontermann-Peipers is the best proof that tradition and the future can go hand in hand.
