I tend to favour a rangefinder for travel these days, especially if travel is the primary objective, not photography. GS645s or Mamiya 6 work well. The little Fuji is very light, and the 6x4.5 format is good enough. The M6 does offer a choice of lenses, but sticking to the standard 75mm means you can hang it under a jacket easily.
I've used a YashicaMat for travel, especially where I will have a little more time. I also find the 'box' packs well as a backup camera.
If photography is not the primary reason for the trip, just pick something that you can carry easily if you do not have a secure storage location. If it is a chore carrying it, you won't want to use it.