I grew up in Berlin, when the wall was still up (it came down when I was in the 4th grade, and we left the summer after I finished 5th grade). We flew out of the city to spend major holidays with family back in the states, but in the eleven years I lived there, I left the city via ground transportation exactly three times (all for class trips). Despite hardly ever leaving the city, I regularly went on camping trips with the scouts where it felt like I was in the middle of the wilderness. I also regularly went on walks through sections of the Grünewald (forest/parkland) near my home, and could get so far in that city noise would completely disappear. People would get lost in the Grünewald in the winter and wander around for days before either finally stumbling out onto a street, dying of exposure, or being killed by wild boars. I don't know any other city on Earth that contains such large tracts of wildlands inside the city.
As for the canals, they're completely different. They are best enjoyed via river boat cruises, not on walks.
>I like kebabs as much as the next guy and it's probably true that you can get the best ones in Berlin, but let's be honest, it's drunk food and often made from questionable ingredients.
I was way too young to be drinking when I lived in Berlin, but they were still my favorite food. I've been back since, and have consumed them both drunk and sober as an adult, and still think that Berliner Dönners are one of the best foods on Earth. I've been all over the world, and I've never had a Dönner Kebab that stacks up to the ones in Berlin. I've eaten Dönner Kebabs and equivalents (Shwarma, Gyros, etc.) all over the middle east and mediteranean (Turkey, Greece, Israel, Bahrain, Dubai, etc.), places where you would expect the Kebabs to be better, but they're not as good as in Berlin. The only thing that came close were some Shwarma I bought from a Lebanese cafe in Cyprus.
There are some things I don't like about Berlin. The biggest is that the public transportation is dirty, and in some places unsafe at certain hours. When I grew up there, the public transportation was clean and safe (as a grade-schooler, I was allowed to range all over the city with my friends, riding the buses and subways with no adult supervision). When I went back to visit for the first time a few years later, I was shocked at how dirty and poorly-kept they had become.