Travel Books for Kids?

Curious if anyone can recommend any travel guides for kids... Europe, North American cities, etc.? I find myself reading travel guides more than regular literature and would like to give my aunt's children (ages 7 and 10) the same opportunity yet there doesn't seem to be much out there to excite travel. If you have a favorite book or series, I'd sure like to know.
Thanks in advance

Miroslav Sasek's "This is *Rome*Hong Kong*Australia*Ireland*Texas*San Francisco etc"
Peter Sis's books.
Joan Knight's "Charlotte in *New York*London*Paris etc"

Any historical fiction tends to be based *somewhere*....that has been enough to spark interest in my kids. In fact, a picture book with a ger in it was enough for one of ours to ask if we could go to Mongolia....and we did!

Actually, don't underestimate the power of kids' picture books, even though your kids are not young. Are you wanting books about America? There are lots!
I must say that for myself, a good novel is more inspiring than a travel guide!

The Magic Treehouse series takes place in several different countries and time periods. There are a few Magic School Bus books that take place in different countries. The Mythomania books teach about Greek mythology in a funny way. There are several Horrible History books; they're fun too.