The Go club Groningen organizes an internal club competition each half year. The strength of players is currently from 11 kyu to 4 dan. The games are with full handicap to enable a good and interesting game for both players. The rate of play is 45 minutes (Fischer time) giving 15 extra seconds per move.
If you want to join contact Bucco, or mail firstname.lastname@example.org
Three teams of Go club Groningen participate in the National Go Competition (www.gocompetitie.nl). Each half-year they compete with teams from other cities during two Saturdays. Games are played without handicap. The rate of play is 60 minutes with 15 seconds byoyomi per move.
If you want to join contact Herman or mail email@example.com
Lots of clubs organize a tournament each year, with the participation of players from the Netherlands and abroad. The Dutch tournament calendar is here: https://www.gobond.nl/evenementen/lijst.
And maybe you want to search for more club information at https://www.gobond.nl/goclubs