What is the surface of XXX made of?
Telecom Telecommunication Tower Heidelberg
Telecom Telecommunication Tower Heidelberg is a 102 meter tall (originally 80m, raised to 102m in the 80s) telecommunication tower built of reinforced concrete in the late 1950s at 49°24′10``N 8°43′51''E on the mountain Königsstuhl near Heidelberg, Germany.
concrete