We like to use Eyewitness Travel Guides to get background on history of the country and city we’d like to visit. They also share mini-itineraries, walking maps and 3D cutaways of not-to-be-missed sights. I like to get the books second-hand because a lot of the sights haven’t changed and the older books have more information, be it some of the hotels, restaurants, etc may be out of date. It’s also very inexpensive to purchase them second hand from Half Price Books or ABE Books for instance.They also have some helpful phrases at the back which I always take a picture of with my phone and try to memorize.
My Mom and I are avid readers. Whenever we are thinking about a new destination, I always do a search for books related to the country to which we are traveling. It makes a nice gift to my Mom (who already has everything she wants!) and allows us to explore some history and customs that shed light on our upcoming experience.