Lower Silesia (Polish: Dolny Śląsk; Czech: Dolní Slezsko, Latin: Silesia Inferior; German: Niederschlesien; Silesian German: Niederschläsing; Silesian: Dolny Ślůnsk) is the northwestern part of the historical and geographical region of Silesia; Upper Silesia is to the southeast. Throughout its history Lower Silesia has been under the control of the medieval Kingdom of Poland, the Kingdom of Bohemia and the Austrian Habsburg Monarchy from 1526.
In 1742 nearly all of the region was annexed by the Kingdom of Prussia and became part of the German Empire in 1871, except for a small part which formed the southern part of the Lower Silesian Duchy of Nysa and had been incorporated into Austrian Silesia in 1742.
Masuria and the Masurian Lake District are known in Polish as Kraina Tysiąca Jezior and in German as Land der Tausend Seen, meaning "land of a thousand lakes." These lakes were ground out of the land by glaciers during the Pleistocene ice age around 14,000 - 15,000 years ago, when ice covered northeastern Europe.
Great geological changes took place and even in the last 500 years the maps showing the lagoons and peninsulas on the Baltic Sea have greatly altered in appearance.
The hilly places in Poland is indeed much, much more - should go well in the Holy Cross Mountains and Pieniny.
In Poland we will also find areas where there is a completely different vegetation and animals.
You can mention here for example, Roztocze National Park and around the seaside.