Kouvola is a Finnish city located along the Kymijoki River and, along with Kotka, one of the centers of the Kymenlaakso province. The city is home to 81,808 people, making it the 11th largest city in Finland. The city covers an area of ​​2,883.29 km2 (of which 325.62 km2 are water bodies) and has a population density of 31.99 inhabitants / km2. Kouvola's neighboring municipalities are Hamina, Heinola, Iitti, Kotka, Lapinjärvi, Loviisa, Luumäki, Miehikkälä, Mäntyharju, Pyhtää and Savitaipale.

In the late 19th century, the Kouvola station village, which belonged to the then municipality of Valkeala, grew into a densely populated community inhabited by railway workers after the completion of the Riihimäki-St. Petersburg line. The Savo and Kotka lines built before the turn of the century, as well as the railway connection to the rapidly industrialized Kuusankoski paper mills, made Kouvola a crossroads station and a business center. The densely populated community, founded in 1917, was separated from Valkeala as its own municipality in 1922. In 1922–1945, Kouvola belonged to the Vyborg province. It received commercial rights the following year and city rights in 1960 as one of the first new cities in Finland. In 1940 and 1944, most of Vyborg County was ceded to the Soviet Union and the remaining areas were formed into Kymen County in 1945. By now, Kouvola had also become an administrative center: from 1955 until 1997, it was the capital of Kymen County.

The new city of Kouvola was born on January 1, 2009, when the old Kouvola, Anjalankoski, Kuusankoski, Elimäki, Jaala and Valkeala merged to form a new city covering most of North Kymenlaakso, which became known as Kouvola after its headquarters. Long before the unification, Kouvola's city center extended to several municipalities; for example, all the agglomerations of Kuusankoski and a small part of Valkeala had grown up in Kouvola. Other large agglomerations in Kouvola are Koria, located on the opposite bank of the Kymijoki River, the main agglomeration of Valkeala, comprising the church village of Jokela and Valkeala, and the southern railway line Myllykoski and Inkeroinen.

Before the merger, Kouvola had three neighboring municipalities, Elimäki, Kuusankoski and Valkeala.