I've traveled over lots of parts of the world, and have worn out lots of shoes on the road. I've worn boots, hiking shoes, tennis shoes, sandals, and about any other sort of shoe you can think of while traveling about. I've found sandals to be a sort of shoe that I can't do without on the road. And the sandals you can buy these days can be very lasting, along with being very comfortable while on the road.
There are all sorts of good sandals for travel: rainbow sandals, reef sandals, chaco sandals, Crocs. Which type of sandal is preferred depends mostly on the wearer. For me, I like a sandal with a heel strap when traveling, so that it can be held nicely in place without slipping. For more rugged trips, this is especially necessary. I went on a rafting trip a couple of years ago, and the sandals I took then were an old pair, and did not have a heel strap. They were slippery when getting on and off the raft, and I would not recommend that for anyone, though the sandals were otherwise comfortable.
As important as the type of strap a sandal has is the material it is made of. I prefer not to wear leather sandals because they are not as good for wet conditions. I am not crazy about sandals with rubber enclosed tops. They tend to hold in odors, and this can be bad when they get wet. To me, something like this would be a perfect sandal for traveling, and it is the type I always keep on hand.
I have found, however, that sandals are not ideal when on long flights. I've had another passenger run over my toes with his luggage, and ended up with a painful break in the nail for the rest of the trip. I usually wear a closed shoe while flying, and carry a pair of sandals. They aren't hard to fit into the luggage, being so flat, so it's really no extra burden. One thing is for sure, I won't travel without a pair of sandals with me. They are the perfect shoe, most of the time.
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