Budapest is the capital city of Hungary. As the largest city of Hungary, it serves as the country's principal political, cultural, commercial, industrial, and transportation center and is considered an important hub in Central Europe. In 2008, Budapest had 1,702,297 inhabitants, down from a mid-1980s peak of 2.1 million, with an official agglomeration of 2,451,418. The city covers an area of 525 square kilometres (202.7 sq mi) within the city limits. Budapest became a single city occupying both banks of the river Danube with the unification on 17 November 1873, of right-bank (west) Buda and Óbuda (Old Buda) together with Pest on the left (east) bank.

Aquincum, originally a Celtic settlement, was the direct ancestor of Budapest, becoming the Roman capital of Lower Pannonia. Magyars arrived in the territory in the 9th century. Their first settlement was pillaged by the Mongols in 1241-42. The re-established town became one of the centers of Renaissance humanist culture in the 15th century. Following nearly 150 years of Ottoman rule, development of the region entered a new age of prosperity in the 18th and 19th centuries, and Budapest became a global city after the 1873 unification. It also became the second capital of Austria-Hungary, a great power that dissolved in 1918. Budapest was the focal point of the Hungarian Revolution of 1848, the Hungarian Soviet Republic of 1919, Operation Panzerfaust in 1944, the Battle of Budapest of 1945, and the Revolution of 1956.

Widely regarded as one of the most beautiful cities in Europe, its World Heritage Sites include the banks of the Danube, the Buda Castle Quarter, Andrássy Avenue, and the Millennium Underground Railway, the first on the European continent. In addition, the largest thermal water cave system in the world was discovered under Budapest in 2008.

The city attracts over 20 million visitors a year. The headquarters of the European Institute of Innovation and Technology (EIT) will be in Budapest.

The neo-Gothic Parliament, containing amongst other things the Hungarian Crown Jewels. Saint Stephen's Basilica, where the Holy Right Hand of the founder of Hungary, King Saint Stephen is on display. The Hungarian cuisine and café culture: for example, Gerbeaud Café, and the Százéves, Biarritz, Fortuna, Alabárdos, Arany Szarvas, Kárpátia and the world famous Mátyás Pince Restaurants. There are Roman remains at the Aquincum Museum, and historic furniture at the Nagytétény Castle Museum.

The Castle Hill, the River Danube embankments and the whole of Andrássy út have been officially recognized as UNESCO World Heritage Sites.

Castle Hill and the Castle District; there are three churches here, six museums, and a host of interesting buildings, streets and squares. The former Royal Palace is one of the symbols of Hungary – and has been the scene of battles and wars ever since the thirteenth century. Nowadays it houses two impressive museums and the National Széchenyi Library. The nearby Sándor Palace contains the offices and official residence of the President of Hungary. The seven-hundred year-old Matthias Church is one of the jewels of Budapest. Next to it is an equestrian statue of the first king of Hungary, King Saint Stephen, and behind that is the Fisherman's Bastion, from where opens out a panoramic view of the whole city. Statues of the Turul, the mythical guardian bird of Hungary, can be found in both the Castle District and the Twelfth District.

In Pest, arguably the most important sight is Andrássy út. As far as Kodály Körönd and Oktogon both sides are lined with large shops and flats built close together. Between there and Heroes’ Square the houses are detached and altogether grander. Under the whole runs continental Europe’s oldest Underground railway, most of whose stations retain their original appearance. Heroes’ Square is dominated by the Millenary Monument, with the Tomb of the Unknown Soldier in front. To the sides are the Museum of Fine Arts and the Palace of Arts, and behind City Park opens out, with Vajdahunyad Castle. One of the jewels of Andrássy út is the Hungarian State Opera House. Statue Park, a theme park with striking statues of the Communist era, is located just outside the main city and is accessible by public transport.

The city is home to the largest synagogue in Europe (Dohány Street Synagogue), the largest medicinal bath in Europe (Széchenyi Medicinal Bath) and the third largest Parliament building in the world, once the largest in the world. The third largest church in Europe (Esztergom Basilica) and the second largest Baroque castle in the world (Gödöllő) are in the vicinity.

Andrássy Avenue with its several sights including the Hungarian State Opera House, the Pest Broadway and the House of Terror.

• Bauhaus in Budapest: walk in Napraforgó Street, row of 22 Bauhaus villas, Pasarét and Újlipótváros
• Buda Castle with the Royal Palace, the Funicular, Hungarian National Gallery and National Széchényi Library, Matthias Church, Holy Trinity Column (a plague column) and Fisherman's Bastion
• City Park with Széchenyi Medicinal Bath, Vajdahunyad Castle, the Timewheel, the Zoo, the Municipal Grand Circus and the Amusement Park
• Danube Promenade or Dunakorzó with Vigadó Concert Hall
• Ferenciek tere with Paris Courtyard and Erzsébet Bridge with Inner City Parish Church nearby
• Franz Liszt Academy of Music
• Gellért Baths, Gellért Hill with Gellért Statue, Cave Church and Citadel with Liberty Statue
• Geological Museum
• Great Market Hall and Liberty Bridge
• Heroes' Square with the Millenary Monument, the Palace of Art and the Museum of Fine Arts
• Margaret Island with the Centennial Memorial, a Japanese garden, a Musical Fountain, several recreation facilities and Franciscan, Dominican and Premonstratensian ruins from the Middle Ages
• Museum of Applied Arts
• National Museum
• Szabadság tér One of the most beautiful squares in downtown Budapest
• Corvin tér Beautifully restored square at the foot of Castle Hill
• Dohány Street Synagogue, the largest synagogue in Europe with the Holocaust Memorial (weeping willow statue)
• New York Café
• Óbuda
• Palace of Arts and National Theatre
• Parliament Building with the Holy Crown of Hungary and sceptre, Kossuth Memorial, Ethnographical Museum, Attila József statue, Imre Nagy statue
• Saint Stephen's Basilica
• Sashegy The largest Natural Reserve Park of Budapest
• Shoes on the Danube Promenade Gyula Pauer - Holocaust Memorial
• Statue Park
• Széchenyi Chain Bridge, Academy of Sciences and Gresham Palace
• Tomb of Gül Baba
• Váci Street and Vörösmarty Square
• Western Railway Station
• Erzsébetváros District VII, the former Jewish quarter