Prague.

Prague is the capital and largest city of the Czech Republic. Its official name is Hlavní město Praha, meaning Prague - the Capital City.
Situated on the River Vltava in central Bohemia, Prague has been the political, cultural, and economic centre of the Czech state for over 1100 years. The city proper is home to more than 1.2 million people, while its metropolitan area is estimated to have a population of over 1.9 million.
Prague is widely considered to be one of the most beautiful cities in Europe and is among the most visited cities on the continent. Since 1992, the extensive historic centre of Prague has been included in the UNESCO list of World Heritage Sites. According to Guinness World Records, Prague Castle is the largest ancient castle in the world. Nicknames for Prague have included "the mother of cities" (Praga mater urbium, or "Praha matka měst" in Czech)", "city of a hundred spires" and "the golden city".

Since the fall of the Iron Curtain, Prague has become one of Europe's (and the world's) most popular tourist destinations. It is the sixth most-visited European city after London, Paris, Rome, Madrid and Berlin. Prague suffered considerably less damage during World War II than some other major cities in the region, allowing most of its historic architecture to stay true to form. It contains one of the world's most pristine and varied collections of architecture, from Art Nouveau to Baroque, Renaissance, Cubist, Gothic, Neo-Classical and ultra-modern. Some of the most known sights are:

Old Town (Staré Město) with its Old Town Square
The Astronomical Clock
The picturesque Charles Bridge
The vaulted gothic Old New Synagogue of 1270.
New Town (Nové město) with its busy and historic Wenceslas Square
Malá Strana (Lesser Quarter)
Prague Castle (the largest castle in the world) with its St. Vitus Cathedral
Josefov (the old Jewish quarter) with Old Jewish Cemetery and Old New Synagogue
Jan Žižka equestrian statue in Vítkov park, Žižkov - Prague 3.
The Lennon Wall
Vinohrady
The museum of Heydrich assassination in the crypt of the Church of Saints Cyril and Methodius
National Museum
Vyšehrad castle
Petřínská rozhledna, an observation tower on Petřín hill, which resembles the Eiffel Tower
Anděl (neighborhood) which is probably the busiest part of the city with a super modern shopping mall and architecture
Žižkov Television Tower with observation deck - Prague 3.
The New Jewish Cemetery in Olšany, location of Franz Kafka's grave - Prague 3.
The Metronome, a giant, functional metronome that looms over the city
The Dancing House (Fred and Ginger Building)
The Mucha Museum, showcasing the Art Nouveau works of Alfons Mucha
Places connected to writers living in the city, such as Franz Kafka (One popular destination is the Franz Kafka museum)

Prague is traditionally one of the cultural centres of Europe, hosting many cultural events.
Significant cultural institutions:

National Theatre
Estates Theatre, premiere of Mozart's Don Giovanni was held there
The Rudolfinum (home to the Czech Philharmonic Orchestra)
State Opera
National Museum
Náprstek Museum
National Library
National Gallery

There are hundreds of concert halls, galleries, cinemas and music clubs in the city. Prague hosts Music Festivals including the Prague Spring International Music Festival, the Prague Autumn International Music Festival and the Prague International Organ Festival. Film Festivals include the Febiofest, the One World and Echoes of the Karlovy Vary International Film Festival. Prague also hosts the Prague Writers Festival, the Prague Fringe Festival, the World Roma Festival as well as hundreds of Vernissages and Fashion Shows.
Many films have been made at the Barrandov Studios. Hollywood movies set in Prague include Mission Impossible, Blade II and xXx. Among others, Czech films Empties and The Fifth Horseman is Fear were shot in Prague. Also, the music video to Diamonds from Sierra Leone by Kanye West was shot in Prague, and features shots of the Charles Bridge and the Astronomical Clock, among others.
Prague restaurant Allegro received the 1st Michelin star in the whole Eastern Europe (post-communist Europe).