Donar, also known as Donar Groningen, is a professional basketball club based in Groningen, Netherlands. The club competes in the BNXT League and its home arena is MartiniPlaza, which has a seating capacity of 4,350 people.

Groningen is the capital city and main municipality of Groningen province in the Netherlands. The capital of the north, Groningen is the largest place as well as the economic and cultural centre of the northern part of the country; as of December 2021, it had 235,287 inhabitants, making it the sixth largest city/municipality in the Netherlands and the second largest outside the Randstad.