If you're traveling to Mexico by air, you'll generally need a valid passport and, depending on your nationality, possibly a Mexican visa. Travelers from many countries, including the U.S., Canada, and most of Europe, can visit Mexico for tourism without a visa for a limited stay. It's also a good idea to have proof of your return flight and accommodation details, as immigration officers may ask for them. Always check the latest requirements before your trip since entry rules can change.