The document provides information about several landmarks and locations in the Czech Republic. It discusses the capital city of Prague, including some of its famous monuments and history. It also describes two national parks - Krkonoše National Park, which contains the country's highest mountain, Sněžka; and Karlštejn Castle, founded in 1348, which served as a residence for several Czech kings and housed the crown jewels. The longest river is identified as the Elbe River.