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forms of ancient glacial accumulation in the shape of oblong hills, with the long axis parallel to the direction of ice movement. They are 5-45 m high, a few hundred meters to 2.5 or more km long, and 150-400 m wide. The core is composed of bedrock or fluvioglacial sands, and the surfaces are moraine deposits. Drumlins are found in groups in regions of ancient glacial development, primarily on plains (for example, in the northwestern part of the East European Plain, south and southeast of the Baltic Shield) and in piedmont regions.