Næstved is an old Danish market town located on South Zealand near the mouth of the Suså. With its 43,803 inhabitants (2020), it is the country's 15th largest city and Zealand's fifth largest city. Næstved is the capital of Næstved Municipality which has 82,883 inhabitants and belongs to Region Zealand. Næstved has 63,194 inhabitants incl. the satellite cities Fensmark, Fuglebjerg, Gelsted, Glumsø, Herlufmagle, Holme-Olstrup, Mogenstrup and Rønnebæk.

The name of the town is formed by the joints næs (protruding land tip) and tved (clearing). Næstved is among the country's oldest towns, and it was founded in 1135 and received market town privileges as early as 1140. In the Middle Ages, it was a large town and among the most important on Zealand. In the 17th century, the town's progress stopped to improve again at the end of the 18th century, when the state barracks, Grønnegades Barracks, was founded. During industrialization, the population grew steadily. A railway and a canal made possible an actual harbor with an outlet in Karrebæk Fjord. In the first half of the 20th century, the city grew.

As the second largest city in the region, Næstved is today a significant trading and industrial city with a large catchment area. It is also an educational city with various youth educations and educational offers for children and adults. Previously, the city was known for its guardhouses, which have now moved to Slagelse. Næstved is a station town and a railway junction between Nykøbing Falster and Copenhagen and has several train connections to other Zealand towns. Likewise, many bus routes in the immediate area are based in Næstved.

Næstved is rich in especially medieval architecture and has several museums and annual cultural events, including the Green Concert. There is also a large theater and music environment. Several major tourist attractions are in the immediate vicinity of the city: the amusement park BonBon-Land and Gavnø Castle. The city has many sports clubs and covers a wide range of sports, as well as sports facilities such as Næstved Arena and Næstved Stadium.