Don't Drink The Water: 8 Places To Turn Off The Tap (Slideshow)
Ask anyone experienced with travel to the Indian subcontinent about water, and they'll tell you not to drink it directly from the sink. The locals may be used to it, but your immune system won't be able to handle the pathogens, making it a virtual lock that you'll be locked in the bathroom instead of enjoying a ride on back of an elephant.
South Africa
I don't know too much about Dave Matthews Band, but apparently they have a song called "Don't Drink the Water." I have no idea what it's about, but since he's from South Africa, my best guess is that he was singing about his homeland, if not the entire continent. While South Africa's bigger cities are safer, heed Mr. Matthews' lyrical advice when treading in less urbanized areas.
San Diego, Calif.
"America's Finest City" may have great ocean waves, but it's known for having hard tap water that's overly abundant in calcium and magnesium. This gives it an unpleasant taste and an unappealing look (especially in a clear glass), so you probably wouldn't want to drink it anyway. If you're unfazed by its aesthetics, let the potentially dangerously high mineral content keep you from chronic consumption.
China
The list of unpleasantries about China's tap water runs longer than your mom's favorite holiday hits boxed set, and includes bacteria-brewing ballads like "12,000 Dead Pigs Dumped in a River," the catchier-than-a-stomach-virus smash "My My, Manganese Mine Residue," and our personal favorite for a stormy Saturday, "Acid Rain Skies Over Sweet Shanghai." Opt for boiled tea or bottled beverages with your noodles and dumplings in the Middle Kingdom.
Russia
With antiquated purification plants across the majority of its major cities, most Russian citizens resort to drinking bottled water — and you should, too, when traveling to their territory. Water sources in St. Petersburg have been found to contain giardia, and most guidebooks and experts will recommend that you avoid having vodka on the rocks in Russia, as ice can be just as menacing.
Mexico
"Montezuma's Revenge" is a term that exists for reasons beyond making you laugh like a kid — it's a serious threat to making your spring break memorable in the worst of ways. Blended drinks like margaritas may seem like the perfect libation to sip on the beach in Cancún, but you're better off taking straight tequila shots to get your buzz on below the border.
Pensacola, Fla.
Since being pointed out for having the worst tap water in the nation a couple of years back, this panhandle city known for top-notch fishing has been working on fixing the issue. That said, it's going to take some time before the locals are convinced. Stick to bottled water if you trek to this neck of the nation.
Las Vegas and Reno, Nev.
It's enough that you'll be wagering big bucks on blackjack and slot machines for you to gamble with your gastrointestinal system in Sin City and its less-sexy cousin. So, stay away from sinks here... unless it's to wash away the dirty feeling after going all-in with pocket aces and losing the hand to the fedora-wearing fish holding queen-ten off-suit. Oh, poker.