In its foundry in Sommevoire, in the Haute-Marne department, GHM manufactures public lightning and cast-iron support masts intended for equipping trams and rail lines. Following time and fashion, the company also started dedicating its production to street furniture in the 1970s, collaborating with innovative designers like Jean-Michel Wilmotte. Today, the foundry produces a wide range of street furniture items, including posts, fountains, benches, tree corsets, music kiosks, or street lamps.