Harrachov (Czech pronunciation: [ˈɦaraxof]; German: Harrachsdorf) is a town in Jablonec nad Nisou District in the Liberec Region of the Czech Republic, close to the border with Poland. It has about 1,400 inhabitants. It is known as one of the most popular Czech ski resorts.

Harrachov consists of four municipal parts (in brackets population according to the 2021 census):

Harrachov is located about 18 kilometres (11 mi) east of Jablonec nad Nisou, on the border with Poland. It lies in the Giant Mountains. The highest point is the mountain Luboch at 1,296 m (4,252 ft) above sea level. Part of the municipal territory belongs to Krkonoše National Park.

The Mumlava River flows through the town. Its confluence with the Jizera is situated on the municipal border. On the Mumlava there is the Mumlava Waterfall, the biggest and one of the most famous waterfalls in the Czech Republic. It has a flow rate of 800 L/s and a height of 8.9 m (29 ft).

Harrachov was established in the 17th century, after a glassworks was founded in the area of Ryžoviště, and originally was called just Dörf (German for 'little village'). During the rule of Count Ferdinand Bonaventura Harrach (1701–1706), the settlement was renamed Harrachsdorf in his honor. The first written mention of Harrachov is from 1720. After a glassworks was founded also in the area of Nový Svět in 1711, the importance of Harrachov grew. The settlements of Nový Svět and Ryžoviště were founded around the glassworks in the mid-18th century.

Since the end of the 19th century, Harrachov has been known for its glass production, textile industry, and mining. At the beginning of the 20th century, industrial production was bolstered by the construction of a cog railway line between Bohemian Tanvald via the Izera railway down to Silesian Hirschberg (present-day Jelenia Góra).

After World War II, the Silesian lands in the north fell to the Polish People's Republic according to the Potsdam Agreement and the border was closed. The German population was expelled and its property seized according to the Beneš decrees.

In 1958, the Communist governments of Czechoslovakia and Poland arranged a territorial exchange. Since the railway station located here was unusable for Poland after the interruption of cross-border traffic (the line to Jelenia Góra returned to Czechoslovak territory in a short section) and the local small settlements were almost inaccessible from the Polish side, the territories was exchanged. Czechoslovakia acquired the area around former Strickerhäuser (Polish: Tkacze, present-day Mýtiny). Poland was compensated by land in western Giant Mountains. In this way Harrachov acquired a railway station.