This literally happened today: a Thai tourist with a 600k watch was snatched right off a famous shopping street in Munich, where it is considered one of the safest cities in Europe. Turns out the thief is a professional and is wanted all over Europe (but I guess never caught so far). While I am sure your watch would not gather that much attention - you never know who is watching. I still remember losing a diamond bracelet when I was traveling, and it still hurts even now… and worse is: I didn’t insure it… so now I only travel with plain or small pave jewelry, unless I’m traveling with my husband. If your watch is a plain gold one, I think it should be ok. If it’s with diamonds and catch attention easily, I would leave it behind. Safe travels and have fun!
Totally irrelevant at this point, but if his watch alone was $600K I can’t help but to envision more jewelry in similar price ranges and I’m thinking he should’ve had a body guard.