I'd say to improvise some workouts to do in your cabin or on a deck with a gorgeous view and think ahead of time about how you're going to eat. Then, just know that when you get back, you will get on your typical program again.
I took a longish trip to Europe a summer ago and while I was there, I didn't eat out a lot and I joined a gym for the equivalent of about $100 U.S. (My hotel didn't have a gym.) I did do a lot of walking while I was there, but I also wanted sweaty cardio. People that I know said that that was crazy, that when you're on vacation you shouldn't think about exercise and you shouldn't do things there that you can do at home. But I think most of those people tend to rationalize away the notion of exercise. Anyway, on that trip, I maintained everything. On other trips of similar or longer duration, though, I lost muscle when gyms weren't available to me, but I picked up a tiny bit of other forms of muscle because of other types of workouts that I did to offset not visiting a gym. It sort of all worked out in the end and when I got back, I got right back on it and redeveloped what little I'd lost.
It's a lot about mindset, I think, and knowing that you might have tiny temporary setbacks. But if your habits are ingrained and if you're dedicated to it for strong reasons, you'll be fine in the long run. Good luck. Enjoy yourself!