Kisangani (/kiːsəŋˈɡɑːni/), formerly Stanleyville (Dutch: Stanleystad), is the capital of Tshopo Province, located on the Congo River in the eastern part of the central Congo Basin in the Democratic Republic of the Congo. It is the country's fifth-most populous urban area, with an estimated population of 1,602,144 as of 2016, and the largest of the cities in the tropical woodlands of the Congo.

Geographically, Kisangani is flanked by Banalia Territory to the north, Bafwasende to the east, Ubundu Territory to the south, and is bordered by both Opala and Isangi Territories to the west. The city spans an area of 1,910 square kilometers and is situated within the equatorial forest plain at coordinates 0°30' north latitude and 25°20' east longitude, just 80 kilometers from the equator. Kisangani is located approximately 2,100 kilometers (1,300 miles) from the mouth of the Congo River, making it the farthest navigable point upstream.

Kisangani is administratively divided into six communes. Five communes—Kabondo, Kisangani, Makiso, Mangobo, and Tshopo—are strategically situated on the right bank, while the Lubunga commune is on the left bank.

Kisangani is the nation's most important inland port after Kinshasa, an important commercial hub point for river and land transportation and a major marketing and distribution centre for the north-eastern part of the country. It has been the commercial capital of the northern Congo since the late 19th century.

Before Henry Morton Stanley, working on behalf of King Leopold II of the Belgians, founded what would become Stanley Falls Station in 1883, the area was inhabited by Wagenya, who used Wagenia Falls (which was formerly named Stanley Falls) for fishing. The station was founded on the Island of Wana Rusari, a few meters from the contemporary site of Kisangani, along the Lualaba River. This area, characterized by its seven falls spanning 100 kilometres (62 mi) between Kisangani and Ubundu, was first traversed by Stanley in 1877 after navigating the rapids and falls that impeded further upstream navigation, mistakenly believing he was descending the Nile River.

He documented that approximately a thousand fish were caught daily in Stanley Falls, each weighing between two and twenty kilograms, with the Wagenya maintaining significant reserves of smoked fish for trade. The trade network extended beyond foodstuffs to include canoes, fishing nets, pottery, wooden utensils, and metallic objects crafted by specialized artisans, often from distinct ethnic groups, such as the Ramangas, renowned for their expertise in canoe and wooden furniture manufacturing.

Stanley returned to the region on 1 December 1883, to establish the initial trading post in the region, situated approximately 2,100 kilometres (1,300 mi) from the Congo River's mouth, following negotiations with Arab-Swahili traders who had settled in the area the previous year. The station, designated as the ultimate destination of the expedition, was commissioned by the Comité d'études du Haut-Congo. Stanley was accompanied by two Scottish engineers, a German mechanic, and a sailor from Stanleyville, with Scottish engineer Adrian Binnie assuming the role of station director.

Initially referred to as Falls Station or "The Post Stanley Falls", "The Falls", or colloquially "Boyoma" (the indigenous name for Boyoma Falls), the settlement was consistently identified as "Kisangani" by the local populace, while Europeans commonly used the French term Stanleyville (or Stanleystad in Dutch). The Swahili language manual published by the Marist Brothers in the 1920s provides an instance of this naming substitution: "from X to Stanleyville" is translated as "toka X Mpaka Kisangani".