What are the general attractions to choose from when traveling to Europe for 20 days?

I think you should ask which cities to go to.

Switzerland is the most expensive, but the scenery is beautiful.

For 20 days, it depends on which area you want to go.

Greece is not recommended, it’s too chaotic and now the police don’t care about you.

In Austria, if you are interested in concerts in Vienna or like Princess Sissi, you can go there for 2 days. It is also good to go to the Golden Hall.

Take the train to Germany, Munich, a very interesting place, beer, music, 2 days, plus you can go to the most beautiful castle Neuschwanstein, 1 more day.

Italy is a good place to spend more time. If you only go to Rome and Venice, the total transportation and other things will take about 6 or 7 days. You can also go to Sicily, but it is more troublesome.

Train to Switzerland. You know the Swiss Alps, but the train to Jungfraujoch is still not cheap.

Train to France. Paris is for sure, although it is a bit boring, 2 or 3 days are always needed. Beware of thieves and scammers. If you are interested, you can choose Mont Saint-Michel Castle, or go to Provence or Nice for 2 days.

The train to Spain is very fast, and we are in Barcelona in a short time. It takes 2 or 3 days. It is definitely worth visiting, including the Sagrada Familia, the park and the Mediterranean Sea. Beware of thieves and scammers. (The time I'm talking about here basically requires running wild).

If you want to go a little further south, go to Madrid (not very interesting, 2 days). You can also go to Granada for 2 days. The Rambla Palace is very good.

Then take the train to Portugal, which is basically Cabo da Roca, but very beautiful, and lasts 2 days.

Well, if you are not interested in these countries. Just go to Northern Europe.

3 days in Amsterdam, Netherlands (including Windmill Village, Giethoorn, Wooden Shoe Village or Cheese Village, I like Windmill Village).

2 days in Copenhagen, Denmark.

Then you can take an evening cruise to Oslo, Norway. Oslo is enough for 1 or 2 days, and then we go to Bergen to see the fjords and glaciers for a round trip, which takes about 2 days.

Stockholm is up to you.

Then go to Finland~ Go to Santa Claus Village Rovaniemi, which takes about 3 or 4 days.

It’s better to go to Northern Europe in winter~unless you want to go to the fjords of Bergen~