To be honest, the Rudolf-Kalweit-Stadion is not actually a lost ground. The stadium is still in use by Arminia Hannover. Fact is that parts of the stadium are taken over by Mother Nature nowadays. Besides that, parts of the wooden main stand are decayed.
The stadium is build and opened in 1918. In 1976 it was renovated and received a new roof coming from Stadion Rote Erde of Borussia Dortmund. It is a beautifull football ground with a lot of character.