Poland

Krakow is a great option for a weekend in a European city

•     Cloth rows and the main market - the heart of the old town
•     Wawel Castle - walk along the Vistula River
•     Białańsko Tyniec Landscape Park - the usual forest, with mediocre attractions - a mound and a zoo

You shouldn't go here specially, only if the way passes nearby. But if you compare Krakow and Wroclaw, then Krakow is definitely the right place for walking).

Wroclaw with its sights is for lovers:

•     Gothic-style town hall - cute, but no more
•     Market square with brightly colored houses - nothing fancy.
•     Statues of gnomes - "they made a mountain out of nothing" - nothing to see.

If you're passing through, you can come here for 1-2 hours, but it's not worth going especially. It is better to visit Krakow, it will be more interesting there.

A comparison of zoos in Europe - is each one worth a visit?

•     Rotterdam's Blijdorp Zoo - Holland - recommended to visit.
•     Prague Zoo - Czech Republic - highly recommended.
•     Krakow Zoo - Poland - not worth a special trip.