Since the last family reunion in 2009, a few things have changed at Castle Grünenstein: The park around the castle has been restored and is now open for the population of the town Balgach. Also a pavilion named Waldpavillon ("Forestpavilion") has been built where the Hermit- or Hunter-house stood previously. The Apéro with music on Sunday will be at this Waldpavillon.
Some more information about the castle can be found here. There is also some more information for everyone who signed up for the Apéro about how to get to the castle and where to park.
