The Czech Republic is a small country in Central Europe with 10 million people living in three main regions. The capital and largest city is Prague, known as the "heart of Europe". Some key landmarks in Prague include Prague Castle, Charles Bridge, Old Town Square with its astronomical clock, and Petřín Hill observatory tower. The city also has many historical buildings and monuments. Outside Prague, the document describes several castles, spa towns like Karlovy Vary, and cities such as Olomouc, along with surrounding villages and natural areas in the Jeseníky Mountains.