This is the restored east, the Kiez that came through the GDR battered and came out the prettiest neighbourhood in Berlin. Three kilometres through Prenzlauer Berg on the gentle slope it's named for, threading the market square, the oldest water tower in the city, and the church that helped bring down a state.
Start at Senefelderplatz and walk north into Kollwitzplatz. Come on a Saturday and the organic market is the whole point — the rest of the week it's a leafy square with a bronze Käthe Kollwitz and very good coffee. South to the round 1877 Wasserturm on its mound, then up Husemannstraße, the Gründerzeit street restored to showpiece gloss for the city's 750th birthday while the real East fell apart around it.
The Kulturbrauerei is the middle of the walk — a brewery block of yellow brick turned over to cinemas and a museum of everyday GDR life. You don't have to go in, but the courtyards are free and worth the detour.
End north at the Gethsemanekirche, where the 1989 vigils drew crowds the Stasi couldn't break. Then back down to Eberswalder Straße, the U2, and Konnopke's currywurst under the tracks.

