This is the 11436th most frequent German word.
spremberg
"Spremberg" is a proper noun referring to a town in Brandenburg, Germany.
In this sentence, 'Spremberg' is used as a proper noun, referring to the name of a specific town in Germany.
Spremberg ist eine kleine Stadt in Brandenburg.
Spremberg is a small town in Brandenburg.
Here, 'Spremberg' is again a proper noun, indicating the destination of the trip being planned.
Meine Freunde und ich planen morgen einen Ausflug nach Spremberg.
My friends and I are planning a trip to Spremberg tomorrow.
In this sentence, 'Spremberger' is an adjective derived from 'Spremberg', describing something related to this town (the city festival).