Geography Lithuania is the largest and most populous of the three Baltic states. The Republic of Ireland is the European country which most closely resembles it in size and population density, having slightly fewer inhabitants in a marginally larger area. According to the calculations of the French National Geographical Institute, Lithuania lies in the exact center of Europe. Lithuanian landscape consists of low-lying planes, which came into existence during the last Ice Age, and hilly uplands form the glacial drift. Huge isolated boulders of rock are another glacial leftover, and can be found in various locations in northern Lithuania.
Lakes are a recurrent feature of the landscape.
There are roughly 3,000 total, with the man-made Kaunas Sea being the largest stretch of inland water. Lithuania's most important river is the Nemunas, which rises in Belarus and empties into the Curonian Lagoon. About a third of Lithuania's population lives in the three major cities of Vilnius, Kaunas, and Klaipeda. Two other cities, Siauliai and Panevezys, trail behind in population. The rest of the population lives in medium-sized and small towns, villages and hamlets dot all over the country.