Simplify the following text for a Grade 10 native English-speaking person.
Original: The district was established in 1994 by merging the former districts of Gardelegen , KlÃ tze , Salzwedel and ( partially ) Osterburg .
Simplified: The modern district was established in 1994 by joining the former districts of Gardelegen , KlÃ tze , Salzwedel and part of Osterburg .