How to swim in the Balkans?

I have experienced Balkan tourism before. According to the travel itinerary of Kaiyuan at that time and the final overall feeling, I would like to give the landlord the following suggestions:

You can go to Lake Brad at the southern foot of the Alps first. Lake Bled is produced by the geological movement of glaciers in the Alps, and the melting water from the snow on the top of "Santou Mountain" is continuously injected into the lake, so it is called "ice lake". Take a boat trip to Lake Brad, see Brad Castle and explore the monastery on the holy island in the lake. After that, I went to Zagreb, the capital of Croatia, and enjoyed the Gothic architecture-Zagreb Cathedral. Compared with St. Kyle's Cathedral in St. Kyle's Square, I feel different church interior and culture. I stood on the observation deck of Lotsakta in front of the Lost Love Museum overlooking the old city.

Then go to Jiuzhaigou in Europe, the oldest national park in Southeast Europe-Sixteen Lakes National Park. Visit different styles of lakes along the river and enjoy rare birds and animals and beautiful scenery. Then visit the historic Croatian city of zadar, and feel the once prosperous city under the gate of zadar built by Venetians. In St. donat's Church, listen to the tour guide to explain the glorious history of ancient Rome and feel the sea breeze, a modern experimental instrument.