Cranes are not a new invention – medieval engineers used elementary ones for some of Europe’s biggest cathedrals. There are all kinds of modern contraptions specially geared to meet the exacting demands of the construction industry. The most common of these is the tower crane – instantly recognisable, the long-reaching arms are an ever-constant feature on modern cityscapes.

Tower cranes are often secured to the ground inside the structure, where airspace around the building is limited. A common modern engineering technique is to fix the crane in place of the lift shaft – moving the crane to higher elevations as the site grows – and converting the shaft once the crane has been dismantled.

The world’s biggest tower crane is the colossal K-10, 000 – built by Danish company, Kroll. Standing 120m tall, with a reach of 90m, it’s five times the size of ordinary tower cranes. It has the capacity to lift two Challenger tanks at full stretch. The K-10, 000 is nearly three times as tall as the Statue of Liberty and its operating range covers seven-and-a-half acres.