The relationship between Carlisle and the town of Flensburg in Schleswig-Holstein dates back to 1960. The first formal exchange visits took place a year later.
Twenty eight Students from Flensburg have begun placements in local businesses and organisations this week to continue promoting friendship between people from both areas.
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Detectives say the men have shown "no remorse for their actions whatsoever".
So far, they've removed more than 20,000 tonnes of gravel.
The festival is one of the longest running Blues festivals in the country.