My experience has been limited (gracias a Dios) to the one in Chelem, where the kids occasionally and quite literally drag us to partake in fun and games and rides too.

Before I launch into the details, try to picture the fair. It's the plaza in Chelem, a half-sand, half-concrete square in the middle of the 'town'. On it, around it and in the middle of it are tarps and ropes covering stands, games, and 'restaurants'. These are all lit up thanks to extensive cables and wires that emerge from tarantula-like knots on the side of the electricity poles and switch boxes and spread out in all directions, snaking across the ground, over your head wrapped around the poles holding up the tarps etc. The restaurants are gas powered and therefore propane gas tanks are always close by, a couple of feet away from the stoves and grills to be exact. There are also rides; contraptions sold off by bankrupt U.S. fairs and theme parks in 1937, or so it would seem. They are all rusted, dented and scratched metal rides; little bashed up Kenworth trucks for the niños that wiggle precariously around a crooked track; or perhaps a 'ferris' wheel that is half a story high, and bears more of a resemblance to a collection of chicken coops strapped to a large vertical wheel that struggles to go round and round thanks to a 289 V-8 puffing away very close by.

All this is made more pleasant by the distorted (is there any other way to put some ambience in a public place in Mexico?) music (endless dance remixes) trying to boom from large black speakers everywhere and the growing collection of half-eaten corn cobs, paper, bottles and other garbage liberally sprinkled about.

That's the general atmosphere. If you want details, here are a few:

Games and Attractions
There are darts and balloons, the former being so dull (as in pointless - ie: unsharpened) and attached to some ancient plastic or prehistoric ostrich feathers that they are uncontrollable upon throwing; the latter so softly inflated that they would never pop no matter what you threw at them. As for the prizes, they only offer one kind of prize, no matter how many balloons you don't pop: posters! That's right, posters. But not the glossy kind you'd see in a shop somewhere in a mall; no, these are special and unicos posters. Sun-bleached (remember no one ever wins these things) photographs or color copies glued onto cheap plywood and covered in plastic shrink wrap to give it that extra touch of glossy class. And the subjects of the photographs? There's the stuff that is current and popular such as multiple poses of Leonardo DiCaprio and maybe a Mexican singer or sopa opera star; and there are the traditional favourites or standards, always guaranteed to please. These range from the classic Virgen de Guadalupe or the little blond girl with the horse to Pamela Anderson and her bared assets. These are all side by side, by the way, and you can actually observe the Virgen kind of frowning upon Pamela's breasts if you get the right light and angle.

Roulette
A more recent addition; a little plastic roulette wheel from one of those game boxes and a hand made betting board are sure to leave you centavo-less in exchange for a moment of excitement and Las Vegas-style glamour.

Loteria
Almost a thing of the past. The traditional beach house kids game taken to the next level a la roulette. Place your coins on the figurita you think will show up on one of three polygons that the master of ceremonies shakes around in a battered box. When they show up, you get paid. If not, it's bye bye pesos.

The Shooting Gallery
You don't win a damn thing and just shoot little lead pellets at the little scratched up metal animalitos and the funny and formerly hairy gorrilla or hula-clad  puppets that dance. Keep an eye on the little ones here since the pellets rebound a lot and tend to hit passers-by. When you do manage to hit the button that activates the formerly hairy gorrilla, you are treated to a blaring and distorted musical interlude accompanied by hyperactive jiggling on the part of the gorrilla. When the person running the 'arcade' tires of the music, he pulls one of several dangling cables to shut the monkey down.

Futobolitos
Every fair has gotta have these - dozens of swaybacked football-soccer tables, with little plastic balls very tired and unsavoury looking plastic players to twirl around. These tables cost around 2 pesos a game (5 balls) and provide probably the only source of what could be called amusement. The early teen set really enjoys this area, and the locals that run the games always put on appropriate music (Molotov, Control Machete - anything where rapping insultos is included) a todo volumen to make the place that much more cool.

All in all, the feria is truly a horrendous non-event but very typical of the temporada and a must-do experience, unless you're a visiting health inspector from some civilized nation in which case you will probably have to be carted away. It is also a helpful reminder to keep us all ubicados, so that we don't become blinded by the Hondas, Audis, Mercedes, Sams, Fridays, McDonalds and Burger Kings and somehow become confused about our national status, the feria de Chelem keeps us firmly rooted in the third world.