Belgrade is the capital and largest city of Serbia. It is located at the confluence of the Sava and Danube rivers and the crossroads of the Pannonian Plain and the Balkan Peninsula. Nearly 1.7 million people live within the administrative limits of the City of Belgrade, a quarter of the total population of Serbia.

Belgrade is one of the oldest continuously inhabited cities in Europe and the World. One of the most important prehistoric cultures of Europe, the Vinca culture, evolved within the Belgrade area in the 6th millennium BC. In antiquity, Thraco-Dacians inhabited the region and, after 279 BC, Celts settled the city, naming it Singidun. It was conquered by the Romans under the reign of Augustus and awarded Roman city rights in the mid-2nd century. It was settled by the Slavs in the 520s, and changed hands several times between the Byzantine Empire, the Frankish Empire, the Bulgarian Empire, and the Kingdom of Hungary before it became the seat of the Serbian king Stefan Dragutin in 1284. Belgrade served as capital of the Serbian Despotate during the reign of Stefan Lazarevic, and then his successor Durad Brankovic returned it to the Hungarian king in 1427. Noon bells in support of the Hungarian army against the Ottoman Empire during the siege in 1456 have remained a widespread church tradition to this day. In 1521, Belgrade was conquered by the Ottomans and became the seat of the Sanjak of Smederevo. It frequently passed from Ottoman to Habsburg rule, which saw the destruction of most of the city during the Austro-Ottoman wars.

In the period after the Serbian Revolution, Belgrade was again named the capital of Serbia in 1841. Northern Belgrade remained the southernmost Habsburg post until 1918, when it was attached to the city, due to former Austro-Hungarian territories becoming the part of the new Kingdom of Serbs, Croats and Slovenes after World War I. Belgrade was the capital of Yugoslavia from its creation in 1918 to its dissolution in 2006. In a fatally strategic position, the city has been battled over in 115 wars and razed 44 times, being bombed five times and besieged many times.

Being Serbia's primate city, Belgrade has special administrative status within Serbia. It is the seat of the central government, administrative bodies, and government ministries, as well as home of almost all of the largest Serbian companies, media, and scientific institutions. Belgrade is classified as a Beta-Global City. The city is home to the Clinical Centre of Serbia, one of the hospital complexes with the largest capacity in the world, the Church of Saint Sava, one of the largest Orthodox church buildings, and the Štark Arena, one of the indoor arenas with the largest capacity in Europe. Belgrade hosted major international events such as the Danube River Conference of 1948, the first Non-Aligned Movement Summit (1961), the first major gathering of the OSCE (1977-1978), Eurovision Song Contest (2008), as well as sports events such as the first FINA World Aquatics Championships (1973), UEFA Euro (1976), Summer Universiade (2009) and EuroBasket three times (1961, 1975, 2005).

Lying on the main artery connecting Europe and Asia, as well as, eventually, the Orient Express, Belgrade has been a popular place for travellers through the centuries. In 1843, on Dubrovacka Street (today Kralj Petar Street ), Serbia's knez Mihailo Obrenovic built a large edifice which became the first hotel in Belgrade: Kod jelena ('at the deer's'), in the neighbourhood of Kosancicev Venac. Many criticised the move at the time due to the cost and the size of the building, and it soon became the gathering point of the Principality's wealthiest citizens. Colloquially, the building was also referred to as the staro zdanje, or the 'old edifice'. It remained a hotel until 1903 before being demolished in 1938. After the staro zdanje, numerous hotels were built in the second half of the 19th century: Nacional and Grand, also in Kosancicev Venac, Srpski Kralj, Srpska Kruna, Grcka Kraljica near Kalemegdan, Balkan and Pariz in Terazije, London, etc.

As Belgrade became connected via steamboats and railway (after 1884), the number of visitors grew and new hotels were open with the ever luxurious commodities. In Savamala, the hotels Bosna and Bristol were opened. Other hotels included Solun and Orient, which was built near the Financial Park. Tourists which arrived by the Orient Express mostly stayed at the Petrograd Hotel in Wilson Square. Hotel Srpski Kralj, at the corner of Uzun Mirkova and Pariska Street was considered the best hotel in Belgrade during the Interbellum. It was destroyed during World War II.

The historic areas and buildings of Belgrade are among the city's premier attractions. They include Skadarlija, the National Museum and adjacent National Theatre, Zemun, Nikola Pašic Square, Terazije, Students' Square, the Kalemegdan Fortress, Knez Mihailova Street, the Parliament, the Church of Saint Sava, and the Old Palace. On top of this, there are many parks, monuments, museums, cafés, restaurants and shops on both sides of the river. The hilltop Avala Monument and Avala Tower offer views over the city. According The Guardian, Dorcol is the one of top ten coolest suburbs and in Europe.

Elite neighbourhood of Dedinje is situated near the Topcider and Košutnjak parks. The Beli dvor (White Palace), house of royal family Karadordevic, is open for visitors. The palace has many valuable artworks. Nearby, Josip Broz Tito's mausoleum, called The House of Flowers, documents the life of the former Yugoslav president.

Ada Ciganlija is a former island on the Sava River, and Belgrade's biggest sports and recreational complex. Today it is connected with the right bank of the Sava via two causeways, creating an artificial lake. It is the most popular destination for Belgraders during the city's hot summers. There are 7 kilometres (4 miles) of long beaches and sports facilities for various sports including golf, football, basketball, volleyball, rugby union, baseball, and tennis. During summer there are between 200,000 and 300,000 bathers daily.

Extreme sports are available, such as bungee jumping, water skiing, and paintballing. There are numerous tracks on the island, where it is possible to ride a bike, go for a walk, or go jogging. Apart from Ada, Belgrade has total of 16 islands on the rivers, many still unused. Among them, the Great War Island, at the confluence of Sava, stands out as an oasis of unshattered wildlife (especially birds). These areas, along with nearby Small War Island, are protected by the city's government as a nature preserve. There are 37 protected natural resources in the Belgrade urban area, among which eight are geo-heritage sites, i.e. Strazevica profile, Mašin Majdan-Topcider, Profile at the Kalemegdan Fortress, Abandoned quarry in Barajevo, Karagaca valley, Artesian well in Ovca, Kapela loess profile, and Lake in Sremcica. Other 29 places are biodiversity sites.

Tourist income in 2016 amounted to nearly one billion euros; with a visit of almost a million registered tourists. Of those, in 2019 more than 100,000 tourists arrived by 742 river cruisers. Average annual growth is between 13% and 14%.

As of 2018, there are three officially designated camp grounds in Belgrade. The oldest one is located in Batajnica, along the Batajnica Road. Named "Dunav", it is one of the most visited campsites in the country. Second one is situated within the complex of the ethno-household "Zornic's House" in the village of Bacevac, while the third is located in Ripanj, on the slopes of the Avala mountain. In 2017 some 15,000 overnights were recorded in camps.