The city of Kazimierz was, until WW2, the predominantly Jewish quarter of the Krakow district. It retains the character too, even though over 70 years have passed.
Walking around the city is easy, the layout is almost on the gridiron format, but not quite. It's also very flat, as you'd expect!
If you follow the tourist route that is contained in the street map of Krakow & Kazimierz (available from the tourist information offices that are dotted around both cities), you'll follow a route between Szeroka (a quaint square outside of the Remu Synagogue) and the Basilica of St. Michael the Archangel at the end of Skaleczna. The route takes you past many important historical sites and various museums, some of which are free to see and others charge a modest entry fee.
As you wander through the streets, you'll notice that some buildings are maintained to a very high standard, whilst many more are not. The reason for the lack of investment in some buildings lies back in WW2. The ownership of the more dilapidated buildings remains uncertain and the current occupants seem to be disinclined to perform any maintenance on this basis. This was explained to us by a chap we met, who had rented office space in Kazimierz, but had four different landlords in only a few years. He ended up with the same landlord he started with! However, there have been many sympathetic restorations and re-purposings of buildings. One I particularly liked was along the narrow alley between Szeroka and Miodowa, where four separate shops had been joined together to form a restaurant. The neat twist here, is that each shop retained its character, so the restaurant had four themed sections, depending upon the previous use for that area.
If you propose to wander around Kazimierz, I'd allow a good few hours, or even a whole day if you like to wander around the various places of interest. If you stay until the evening, there are plenty of places to eat and drink. There are even a couple of places that are devoted to various types of street food, so you have a fantastic choice!