Bagger 288

The Bagger 288 is one of the largest machines ever made.

wiki It was built for the job of removing overburden prior to coal mining in Hambach, Germany. It can excavate 240,000 tons of coal or 240,000 cubic metres of overburden daily — the equivalent of a football field dug to 30 meters (98 ft) deep. The coal produced in one day fills 2400 coal wagons. The excavator is approximately 240 m long and 96 m high. The Bagger's operation requires 16.56 megawatts of externally supplied electricity.1 It can travel 2 to 10 m (6 to 30 ft) per minute (0.1 to 0.6 km/h). The chassis of the main section is 46 meters (151 feet) wide and sits on 3 rows of 4 caterpillar track assemblies, each 3.8 m (12.5 feet) wide. The large surface area of the tracks means the ground pressure of the Bagger 288 is very small (17.1 N/cm2 or 25.8lb/in2); this allows the excavator to travel over gravel, earth and even grass without leaving a significant track. It has a minimum turning radius of approximately 100 meters, and can climb a maximum gradient of 1:18.

In this picture you can see the machine while it's on the move towards another excavation site. It really give a sense of the huge scale of the machine. Here are some more pictures. And here is Google Earth kml file where you can see a couple of these machines in the open pit mines. Courtesy of Google Sightseeing.