The Iron Pillar of Delhi is a nearly 24-ft. iron pillar that is located in the Quwwat-ul Mosque. It weighs more than 6 tons and is made of 98% wrought iron. It is thought that the Iron Pillar of Delhi was crafted using forge welding. The pillar is ornate, but hardly awe-inspiring, unless one knows just how long and mysterious the history of it is.