FC Groningen was founded in 1971. Its first home stadium was Stadion Oosterpark. Since 2005, the club has played at Euroborg (the green cathedral). In 1915, a couple of locals inspired by the English players established football club Unitas. When they joined the Groningen Football Association in 1917 they were asked to change their name because there already existed several other clubs in the country named Unitas. The team changed its name into GVAV (the Dutch acronym for “Groningen Football and Athletics Association). In 1970, GVAV’s financial woes worsened when the club relegated from the Eredivisie. In June 1971, FC Groningen was officially established. GVAV’s traditional blue, white and red were dropped in favor of the municipality colors green and white. FC Groningen had their first successes in the 1980s, led by the Koeman brothers Erwin and Ronald. In 2015, they won their first Dutch Cup. The first crest of FC Groningen showed an abstract character “G” referring to Groningen. In 1993, the mythical flying horse Pegasus was added to the crest. The supporters opposed this change and the crest was restored to its original form in 1996. Having no other teams of a similar size in its nearest proximity, FC Groningen lacks traditional rivals. SC Veendam was the nearest professional team to Groningen until the club dissolved in 2013, but as Groningen and Veendam were in different divisions during most of their histories, Veendam had a significantly smaller following, a strong two-sided rivalry never developed. Since the late 1990s a more local rivalry has developed between FC Groningen and Heerenveen, which is just 60 kilometers from the city of Groningen. Therefore, the match between Groningen and Heerenveen is referred to as the Derby of the North.