Yes, people have been known to dress up like portable bathrooms to run in the Bayou City Classic 10K.

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What would you think if you saw a porta-potty running down the street? How about six of them? And they're being chased by a group of nuns, who in turn are being chased by a gorilla, Elvis and Jesus Christ? What would you think?

Nothing, perhaps, if you're near City Hall in Houston on the right day in March each year.

The HEB Bayou City Classic 10K Run and Walk is part road race, part costume party. Since its inception as the Bayou City Fun Run, runners have adorned wild-looking getups that, according to some reports, included a runner dressed as a gorilla carrying a man in a cage. It's Halloween in March minus the candy.

Have you ever seen one of those Chinese dragon costumes? You know, the ones that take four or five people to wear because they're so long? You're bound to see something like that, too. Centipede teams consisting of at least six runners compete in a category of their own [source: Bayou City Classic]. Competing as a group is one thing, but in order for a centipede team to be scored as such, each of the six or more runners must be attached in some way, forcing them to at least consider some prerace training and strategy.

Of course, plenty of runners show up with intentions of winning the race, too. Distance running is a popular sport that many people take seriously. But unlike a marathon, which is 26.2 miles (42.2 kilometers) long, 10Ks are more appealing to the masses. And they're easier to run in a blue gorilla suit, especially in March when the heat and humidity have yet to lay waste to the city. And that's what makes the Bayou City Classic so unique. You never know what you'll see.

Anyone can participate. Registration is between $23 and $30 depending on when you sign up. Unlike some marathons with 70,000 applicants and 30,000 runners, the Bayou City Classic doesn't have a waiting , and there aren't so many people that you run over each other. About 3,000 people turn out for the race.

There are 10K races in many major cities, and for each, the course plays a big part in why people choose to take part in a particular event.. In the next section, we'll take a look at the route runners cover, and we'll get into more of the costume stuff a bit later.