Geography of Poland today's modern Polish society. The ancestors of today's Poles, the Polanie, built their first fortresses on islands in these lakes. The legendary Prince Popiel ruled from Kruszwica tower erected on the Lake Gopło. The first historically documented ruler of Poland, Duke Mieszko I, had his palace on an island in the Warta River in Poznań. Nowadays the Polish lakes provide a location for the pursuit of water sports such as yachting and wind-surfing. The Polish Baltic coast is approximately long and extends from Świnoujście on the islands of Usedom and Wolin in the west to Krynica Morska on the Vistula
Mieszko I Tanglefoot Casimir II's eldest son, Leszek the White. Both sides clashed in the bloody Battle of Mozgawa (Mozgawą) near Jędrzejów (13 September 1195), where Mieszko III was seriously injured and his son Bolesław of Kuyavia died. The Silesian troops, led by Mieszko and Jarosław, arrived to the battlefield too late, soon after Mieszko III withdrew to Kalisz. Despite the forces of the Count palatine Goworek who also arrived to help Leszek's troops, the Silesians obtained a great victory; however, because Mieszko III wasn't present, this victory brought to them only benefits in terms of prestige (not counting the ransoms obtained by