I visited Düsseldorf for the first time a couple of years ago with a friend from Art University who used to study there. Now around fifteen years later I realised that the city hosts the largest Japanese colony in Europe.
For that reason we enjoyed the city with alle the shops and restaurants as much as we did fancy the hanami spring-event. We stayed in a NH Japanese Hotel had Osaka Udon and the best mochi in town. The kids were well dressed up and the setting at the river with all the gathering was quite enjoyable.