The dialect spoken at Kassel, Germany isn’t very strong in everyday life. There are some strangely derived words like for example ‘ahle‘ for ‘old‘ (as used in ‘Ahle Worschd‘, the local speciality). And older inhabitants of Kassel (‘ahle Kasseläner‘) might use them. With the younger generation it seems to be different.
You can easily recognize one of them by their extensive usage of the word ‘als‘ which normally translates as ‘as‘, ‘when‘ or ‘while‘. In northern Hesse the word ‘als‘ is used in the sense of ‘always‘. A sentence like ‘als mähe ich den Rasen‘ means ‘I always cut the grass‘. Another uncommon usage can be observed with the word ‘rammeln‘ which typically describes the sexual intercourse of rabbits, but here it is used for ‘moving somewhere‘. The sentence ‘ich bin hingerammelt‘ means ‘I went there‘.
Kasselänisch is also special because of the geographical position of Kassel. North of the city there is the ‘Benrather Linie‘ or ‘maken-machen-Linie‘ that goes from Krefeld to Frankfurt an der Oder. It separates the clear standard German from the Low German (which isn’t a deprecative naming). In the east of Kassel the federal states of Thuringia and Saxonia can be found with their strong dialects.
A very good source about ‘Kasselänisch‘ is the ‘Digitales Wörterbuch der Kasseler Mundart‘ which can be found at: http://www.dwkm.de