There are two different “Kreuzbergs” in Berlin: one is in the geographical West, one is in the geographical East. They seem worlds apart from each other, not only due to their distance (it often feels as if the Kreuzberg of Schlesische Straße and Kottbusser Tor is closer to Friedrichshain than the Kreuzberg of Viktoriapark, which can be easily confused as part of Schöneberg).
For locals, the difference is a cultural one: Kreuzberg 36 (derived from the former postcode SO36 – Südost 36) is the former punk neighborhood, where Turkish guest workers had to live near the Berlin Wall in cheap and ramshackle housing. Kreuzberg 61, on the other hand, has always been more grown up.
I’ve never really taken the chance of exploring the areas around Bergmannkiez and Viktoriapark. It’s rather laid back and definitely more chic. It reminds me a lot of Prenzlauer Berg. It feels more… finished. Less gritty. Not as dirty. But perhaps that’s just my perception.