It sounds like you had a wonderful time in Krakow, Poland, and I'm glad you got to experience the autumn colors there. I've always wanted to visit Krakow, and it's now on my list of places to see in the autumn.
I love the way you described your walk through the park, and I can imagine how beautiful it must have been with the mix of green, yellow, and brown leaves. I also like the way you compared the park to a green shield that protects the Old Town. It's a very apt description.
I'm also glad that you were able to experience the Jewish quarter in Krakow. It's a very important part of the city's history, and it's a great place to learn about the Jewish culture and heritage.
RE: Finally autumn - but we had to travel to Poland to feel it!