Dear Meimei - All big cities in the whole world - have bad places in their town's - ask local people where to stay in safe placers for you and your bikes. And in Scandinavia contact tourist offices about campsites - Take care🤩🤩😎
i have a suggestion to prevent your bike from being stolen. You can try to search a safety device which has in-built gps to prevent the thief. i believe china would have it, after you install in your bike, you will always able to know the location of your bike while you lodge a police report.