Is there a entrance fee?

There us a suggested payment, but you pay what you want.

You can pay whatever you want, but it certainly is worth paying the full admission price. That being said, it can be expensive if you have a large family so you can pay whatever you can afford. If you want to skip the admission lineups just download the app and buy your tickets in the app. You'll get an e-ticket which will get you into the exhibition halls immediately. But then you have to pay the full suggested amount.