Check the U.S. Government's document requirements to get back to the U.S. after skiing or riding in Canada. 

No, you will not need an American passport, although that's the best form of ID, but border control officials will want to see other proof of identity. However, if you don't have a passport, this will be:

1) a government-issued photo ID such as a driver's license and a birth certificate or other proof of citizenship. Youths 18 and under need only a birth certificate;

Or 2) a valid passport, NEXUS card, SENTRI card, FAST card, U.S. Coast Guard Merchant Mariner's Card, Military ID and Orders, or a Green Card.

U.S. Customs and Border Protection officials will begin to require a valid passport or passport card at some time in the future, but not yet.

The initial deadline for travelers to have passports was early 2008, but a huge number of requests for passports swamped the agency and forced a change in the rules, as outlined above.

Documents aren't the only concern when traveling over the border. Most Canadians speak English, but it's not the most common language in Quebec, where on parle Francais. The money is different, but the same. Canadian dollars are called looneys after the image they sport of a common loon.

At least one popular mapping program has trouble near the border. Recent travelers who programmed their GPS device for a trip to [R307R, Owl's Head] in the Eastern Townships found themselves led along smaller and smaller roads, that finally turned to dirt, rounded a curve, and came to a chain link fence festooned with signs warning of dire consequences should anyone approach closer to the international border.

Getting there, as they say, is half the fun.