The central station location (Hauptbahnhof) is noted for becoming a centre for homeless persons and drug consumers. The specific situation has improved, but you may nonetheless once in a while be bothered by beggars. The drug addicts normally don't hassle individuals, plus the beggars will ask for Kleingeld (modest alter), https://gesundheitalert.de/die-gesundheitlichen-vorteile-von-e-scootern-fur-senioren/