MEXICO’S COPPER CANYON TRAIN - All Aboard: The Complete North American Train Travel Guide - page 250

time I used it was when I crossed the border from El Paso. The
Mexican immigration officer looked at me and said in flawless
English, “And why not, may I ask?” Then, with a big grin, he
said, “But welcome to Mexico anyway, señor.”)
Paying for Things
Change most of your cash into pesos before you cross the bor-
der and, when you do, make sure you get plenty of bills in small
denominations. Large notes can be hard to change, even in some
hotels. You won't be able to use your credit cards onboard the
train—use either pesos or U.S. dollars—but credit cards will
be accepted in virtually all the hotels and in most (but not all)
restaurants.
What to Wear
Dress comfortably by all means, but be prepared for real swings
in temperature along the Copper Canyon route. After all, Chi-
huahua is situated in a desert environment—the highest point
along the way is over 8,000 feet, and Los Mochis, at the other
end of the route, is at sea level. The “layered look” is probably
the way to go.
Health and Safety
The best advice I can offer—and it applies wherever in the world
you may be traveling—is to use common sense when it comes to
where you go and what you do. I doubt you would venture alone
into strange areas of New York or Los Angeles, so don't do it
anywhere else.
When it comes to health issues, there are some basic precau-
tions you should take—not so much because there's any kind of
serious risk, but because they're simple and easy and could save
you a great deal of discomfort and inconvenience.