generate questions: Bern is built on very uneven ground. There is an elevation difference of several metres between the inner city districts on the Aare (Matte, Marzili) and the higher ones (Kirchenfeld, Länggasse).
What type of ground was Bern built on? {sep_token} What is the elevation difference between the inner cities and the other cities? {sep_token} Which city is higher, Matte or Langgasse? {sep_token}