Sofia was originally a Thracian settlement called Serdica, named after the Thracian tribe Serdi. Around 500 BC another tribe settled in the region, the Odrysi, known as an ethnos with their own kingdom. For a short period during the 4th century BC, the city was possessed by Philip of Macedon and his son Alexander the Great.

Around AD 29, Sofia was conquered by the Romans and renamed Ulpia Serdica. It became a municipium, or centre of an administrative region, during the reign of Emperor Trajan (98-117).
The first written mention of Serdica was made by Ptolemy (around 100 AD).
The city expanded, as turrets, protective walls, public baths, administrative and cult buildings, a civic basilica and a large amphitheatre called Bouleutherion, were built. When Emperor Diocletian divided the province of Dacia into Dacia Ripensis (on the banks of the Danube) and Dacia Mediterranea, Serdica became the capital of Dacia Mediterranea. The city subsequently expanded for a century and a half, which caused Constantine the Great to call it "my Rome".

Serdica was of moderate size, but magnificent as an urban concept of planning and architecture, with abundant amusements and an active social life. It flourished during the reign of Byzantine Emperor Justinian I, when it was surrounded with great fortress walls whose remnants can still be seen today.

The city was destroyed by the Huns in 447 but was rebuilt by Justinian and renamed Triaditsa.

Sofia is one of the oldest capital cities in Europe, blending its past and present in a remarkable architectural style. Historic landmarks include the 10th-century Boyana Church (one of the UNESCO World Heritage protected sites), the Alexander Nevski Cathedral (one of the world's largest Orthodox churches), and the early Byzantine Church of St Sophia.

More modern architecture is represented by the Bulgarian National Opera and Ballet, the Ivan Vazov National Theatre, the Rakovski Str theatre district, Slaveykov Square's outdoor book market, and the NDK, which is Southeastern Europe's largest cultural and congressional centre.

There are 16 universities in the city, among them Sofia University, founded in 1888. Sofia is the see of an Eastern Orthodox and of a Roman Catholic diocese.

The city also offers many places of special interest such as the Sts. Cyril and Methodius National Library (which houses the largest national book collection and is Bulgaria's oldest cultural institute), the Sofia State Library, the British Council, the Russian Cultural Institute, the Polish Cultural Institute, the Hungarian Institute, the Czech and the Slovak Cultural Institutes, the Italian Cultural Institute, the French Cultural Institute, Goethe Institut, Instituto Cervantes, Open Society Institute, along with Sofia Land, the nearly nine-acre amusement park adjacent to the Sofia Zoological Garden founded in 1888.

Sofia currently enjoys a booming film industry as it is the filming ground of several international film productions. Vitosha Boulevard, also called Vitoshka — ranked as the world's 22nd most expensive commercial street — represents numerous fashion boutiques and luxury goods stores and features exhibitions by world fashion designers. Sofia's geographic location, situated in the foothills of the weekend retreat Vitosha mountain, further adds to the city's specific atmosphere.

After the Liberation of Bulgaria from Ottoman rule in 1878 and the establishment of an autonomous Bulgarian monarchy with its capital in Sofia, Knyaz Alexander Battenberg invited architects from Austria-Hungary to shape the new capital's architectural appearance.


Among the architects invited to work in Bulgaria were Friedrich Grünanger, Adolf Václav Kolář, Viktor Rumpelmayer and others, who designed the most important public buildings needed by the newly-reestablished Bulgarian government, as well as numerous houses for the country's elite. Later, many foreign-educated Bulgarian architects also contributed.

The architecture of Sofia's centre is thus a combination of Neo-Baroque, Neo-Rococo, Neo-Renaissance and Neoclassicism, with the Vienna Secession also later playing an important part.

Among the most important buildings constructed in Sofia in the period are the former royal palace, today housing the National Art Gallery and the National Ethnographic Museum (1882); the Ivan Vazov National Theatre (1907); the former royal printing office, today the National Gallery for Foreign Art; the National Assembly of Bulgaria (1886), the Bulgarian Academy of Sciences (1893), etc.

After the Second World War and the establishment of a Communist government in Bulgaria in 1944, the architectural line was substantially altered. Socialist Classicism public buildings emerged in the centre, but as the city grew outwards, the new neighbourhoods were dominated by many Communist-era tower blocks (panelki) and examples of Brutalist architecture.

After the abolishment of Communism in 1989, Sofia has witnessed the construction of whole business districts and neighbourhoods, as well as modern skryscraper-like glass-fronted office buildings, but also top-class residential neighbourhoods.

As the country's capital, Sofia is also the most important centre of education, with most of Bulgaria's key higher education institutions being located there. The Saint Clement of Ohrid University of Sofia is often regarded as the top university of Bulgaria, being founded in 1888 and having 14,000 students each year. Other important universities include the Technical University of Sofia, the University for National and World Economics, the Sofia Medical University and New Bulgarian University.

Furthermore, institutions of national dignity, such as the Bulgarian Academy of Sciences and the SS. Cyril and Methodius National Library are also based in Sofia, as are many of the most prestigious schools, like the American College of Sofia, founded in 1860 and regarded as the oldest American educational institution outside the United States.