 Here is a comparison, side by side, of a drag line and a shovel. Bucyrus-Erie is the American company which makes many of these machines. These pictures don't show the relative size of each; the shovel is actually much smaller. Drag lines can be a whole lot larger simply because the boom and arm of a shovel can't be supported if they get too large. 
 The walking drag line on the left above is the Bucyrus model 2570WS, which has a bucket capacity of up to 120 cubic metres (160 cubic yards), and a boom length of 120 metres (400 feet). It can scoop up a single load weighing up to 360,000 kg, or 360 tonnes (400 tons). The machine itself weighs 7,200,000 kg (16,000,000 lbs). The shovel on the right has a 122,000 kg (122 tonne) bucket payload, only a third as big, but still respectable! Our research described many drag lines and large shovels built in the USA during the latter part of the 20th century, and the whereabouts of many of them are kept track of by people who are fascinated by these huge machines. Many of these pieces of equipment are given names, and people come from all across the country to watch it work and to take photographs; when an old one is no longer in use, support groups form to help raise money for its preservation.  One of the largest and most famous American-built shovels was the enormous Silver Spade, seen here crossing a highway. Its size (although not its payload) rivals that of some drag lines. The Spade first went into operation in November 1965; the machine is now in service in Ohio. The Harrison Coal & Reclamation Park has plans to move their museum to the Spade when it shuts down, and make it part of their exhibit.
Specifications: Height: 67 m (220 ft) Boom Length: 61 m (200 ft) Bucket capacity: 79 cubic m (105 cubic yards) Bucket load: 145 tonne (160 tons) Machine weight: 6,400 tonnes (14,000,000 lbs) The Silver Spade, like all shovels, moves itself around on crawlers like a tank or bulldozer, except that the crawlers are much larger. The Spade has three double sets on each side, each one being 34 feet long and 8 feet high; individual pads on the tracks weigh about 2 tons each. Here are some photos of the Silver Spade in operation ... 
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