Check out convict conditioning (or any other bodyweight exercise routine) in the /fit/erature sticky. If you only have one relatively light dumbbell, you might as well just do bodyweight exercises. However, here are some other ideas
1)Find a corner for dips (you can put the dumbbell between your legs for more resistance)
2)find a bar, tree, ledge, whatever for pullups and chinups. Again, the dumbbell can be used if bodyweight is too light for you. Also, if you find a bar, you can throw your legs over it and hang upside down to do hanging situps/crunches.
3)weighted pushups. I'm assuming you'll have a backpack of some sort. Put the dumbbell and any other heavy stuff in it and push away. If normal pushups are too easy, here's some alternatives
http://www.artofmanliness.com/2009/07/21/push-ups-exercises/
4)If you're strong enough and are vacationing with a friend/family, you can fireman carry someone and squat them. I used this method with a friend when I was at ski camp. The person you squat needs to be lighter than what you usually squat since there's unequal weight distribution and less stability with a person. Also make sure they're being carried as high up near the traps as possible.
5)???????
6) PROFIT
If all else fails, just take it easy and relax. It's only 12 days, you won't lose a shit ton of gains. My grad trip was 8 days of clubbing, drinking, insufficient sleep, and only 2 meals a day (due to staying out so late we slept in pretty late too). My squat went down 5 kg, but I brought it back up in 2 weeks (strength 5x5 program).
1)Find a corner for dips (you can put the dumbbell between your legs for more resistance)
2)find a bar, tree, ledge, whatever for pullups and chinups. Again, the dumbbell can be used if bodyweight is too light for you. Also, if you find a bar, you can throw your legs over it and hang upside down to do hanging situps/crunches.
3)weighted pushups. I'm assuming you'll have a backpack of some sort. Put the dumbbell and any other heavy stuff in it and push away. If normal pushups are too easy, here's some alternatives
http://www.artofmanliness.com/2009/07/21/push-ups-exercises/
4)If you're strong enough and are vacationing with a friend/family, you can fireman carry someone and squat them. I used this method with a friend when I was at ski camp. The person you squat needs to be lighter than what you usually squat since there's unequal weight distribution and less stability with a person. Also make sure they're being carried as high up near the traps as possible.
5)???????
6) PROFIT
If all else fails, just take it easy and relax. It's only 12 days, you won't lose a shit ton of gains. My grad trip was 8 days of clubbing, drinking, insufficient sleep, and only 2 meals a day (due to staying out so late we slept in pretty late too). My squat went down 5 kg, but I brought it back up in 2 weeks (strength 5x5 program).