a few years back my wife and I went to Scandinavia for a couple weeks. We brought a small duffle bag of food and did lots of research where we were able to resupply and have meals in kosher restaurants or for Shabbat.
We brought frozen meals - knowing we'd have a fridge and microwave at our destination - and self heating meals, plus cookies, crackers, and other non perishables for constant snacking.
my experience with this trip actually inspired me to start YeahThatsKosher.com. I'm hoping you could all contribute with your experience and expertise as well.