December 12 Day of the Virgin of Guadalupe
The Virgin of Guadalupe is considered "The Mother" of Mexico, the patron saint of the country. Her image is everywhere, from cartoon images on Kleenex boxes to somber paintings that adorn the interior of neighborhood buses. She's honored with several processions, altars all over town, and fireworks.
December 16 The Posadas
"Posada" means "shelter" in Spanish, and this succession of parties represents the efforts of Joseph and Mary to find an inn at which to sleep. The Posadas begin on the 16th of December. Traditionally, visitors carrying candles arrive in procession at a particular house and sing a song requesting entrance. The homeowner sings "sorry, no, we don't have any room" and the song continues in this way until finally the travelers are allowed in.
The less religious skip that part and start the party inside, typically quenching their thirst on Mexican drinks such as ponche and atole and feasting on tamales and pozole. Children are often treated to a piñata at some point in the evening.
This scenario is repeated every evening for the next eight days. In addition to posadas at private homes, the city hosts public posadas which begin from various churches and wind through a different neighborhood each night.
December 24, Christmas Eve
The final public posada ends at the Jardin, where a live manger scene has been set up. Midnight masses are held throughout the city, and like most Mexicans, you'll probably want to spend the rest of the night eating and enjoying the evening with friends and family.
December 25, Christmas Day
A few restaurants serve Christmas dinner, and you can always go to church, but most of the "big" activities of Christmas have passed. Relax. Rest up for New Year's.
December 28, Day of the Innocents
The "April Fools Day" of Mexico, this was originally a day to commemorate the innocent boys who were murdered during Herod's reign in his effort to eradicate any threats to his throne.
Practical jokes abound, such as turning back the clock, gluing coins to the ground, and sticking little paper men on someone's back. Watch out for the borrowing of items/$ never to be returned. Consider yourself warned!
December 31 New Year's Eve
All of the special dinner and dance events you might expect are held tonight, in restaurants, hotels, private homes, and (you guessed it) the Jardin. Things start picking up about 10:30pm, and by midnight the square is packed with revelers of all ages, dressed in everything from jeans to tuxedos, drinks and party blowers at the ready.
The New Year is counted down and welcomed in with a grand display of fireworks, and everyone goes home happy.
Don't forget the grapes! To take part in an old Mexican tradition, buy a bunch to share with your friends. At midnight, eat one at each stroke of the clock for good luck in the coming year.