Achterhoek (Dutch Low Saxon: Achterhook) (literally in English: back-corner) is a region in the province of Gelderland in the Netherlands. It consists of the eastern part of Gelderland, behind the IJssel river, except for the southwestern part, which consists of the region of (De) Liemers. The Achterhoek region borders the Salland and Twente regions (both province of Overijssel) in the north and the German state of North Rhine-Westphalia in the (south)east.
The Achterhoek lies in the Dutch Low Saxon language area and has a dialect of his own called Achterhooks.
Another name for the Achterhoek is the County of Zutphen, which was historically connected to Guelders
Significant towns include Aalten, Borculo, Bredevoort, Doetinchem, Eibergen, Geesteren, Groenlo, Hengelo, Lichtenvoorde, Neede, Silvolde, Varsseveld, Vragender, Winterswijk, Zelhem, and Zutphen.
Doetinchem, Winterswijk and Zutphen are the largest towns in the Achterhoek.