Delfzijl is a city and former municipality with a population of 25,651 in the province of Groningen in the northeast of the Netherlands. Delfzijl was a sluice between the Delf and the Ems, which became fortified settlement in the 16th century. The fortifications were removed in the late 19th century. Delfzijl is the fifth largest seaport in the Netherlands, and the largest port in the North East of the country.

Groningen is the northeasternmost province of the Netherlands. It borders on Friesland to the west, Drenthe to the south, the German state of Lower Saxony to the east, and the Wadden Sea to the north. As of January 2023, Groningen had a population of about 596,000, and a total area of 2,955 km2 (1,141 sq mi).