
I've mentioned it in previous posts, but it's such a big deal for travelers that here's another reminder: By June 1, 2009 you'll need a passport to cross the border between the U.S. and Canada.
Both American and Canadian citizens will either have to show a passport or other federally approved ID to enter the US through land or sea borders. That means if you're traveling by car, train, ferry or cruise ship you need to have the proper documentation. Currently, it's only required for passengers traveling by air.
One of the best explanations of the new requirement is by Kristin Jackson of The Seattle Times.