Multiple days biking tour in the Summer is a nightmare to me! Why? Well, I suffered like hell last summer when I was on a multi-day tour to Hadrian's cycle-way. The friction between the warm road and my rear wheel punctured its tube in the middle of nowhere. That was the most irritating experience in my life, maybe.
After that, I found my solution. I switched for tubes come with self-healing and butyl rubber. Butyl rubber is the main considering fact for strength and durability. The main feature is it provides puncture resistance. Now, I'm planning for another multi-day trip to cover almost 170+ miles.