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Poland is mostly a lowland country. About 90% of the country, especially its central and northern parts, lies at elevations less than 300 m above sea level. The remaining territory are highlands that lie at elevations of 300-612 m, and mountains that usually lie at elevations of up to 1,200 m, with the highest peak at 2,499 m. The division of Poland into hydrogeological regions is linked to the geographic division of Poland. The Hydrogeological Atlas of Poland (Paczynski, 1995) identifies three regions: lowland, highland, mountain. A newer and more detailed system of classification identifies 161 bodies of groundwater in Poland (Paczynski and Sadurski, 2007).
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Chełmicki et al. (2011) studied this question.
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