I am doing the usual route of Thailand, Cambodia and Vietnam and want to avoid places crowded with tourists where it is no doubt beautiful but everyone is just boozing.
I've got two, and they should be avoided for very different reasons.
#1 - Pattaya, Thailand
Pattaya is a filthy hellhole of neon and sex. I'm no prude, but there really aren't any redeeming qualities to this place. The beach is dirty, and quite rundown by Thai standards. The food is horrible, with Thai cuisine taking a back seat to garbage fryups and rubbery seafood that is anything but local.
Pattaya has long had a reputation as a center of sin, which in this context basically means sex. The streets are crowded with bars advertising their services, which run the gamut in terms of the sex trade. Many of the girls advertising these services are in their teens, and they often look young enough that they should really be in school rather than indirectly or directly engaged in the sex trade.
Hey, maybe this is your cup of tea, but I'd recommend avoiding it. There are plenty of places in Thailand with nicer beaches, better food, and more cultural activities to engage in.
#2 - Vang Vieng, Laos
Okay, so the issues here are significantly different than those in Pattaya. Vang Vieng is admittedly very beautiful:
I'm sure it's entirely possible to go here and have a wonderful time exploring the outdoors. So why do I recommend avoiding it? Because of this:
Tubing down the river is the thing to do in Vang Vieng, and Western tourists backpacking through Southeast Asia flock there in droves. Now, tubing could be a really pleasant activity. It could be a nice, quiet day along the river. Instead, the riverside is packed with bars blasting top 40 hits, destroying whatever sense of serenity might have been created by the area's natural splendor.
People generally start tubing relatively early in the day, and by late afternoon have made their way back into town, having had quite a bit to drink by that point. Everything in town is dedicated to continuing the activities from earlier in the day, only perhaps taking them a step further:
Note the prices here: 100,000 kip is about $12 USD. Tourists have been known to lose weeks to Vang Vieng, trapped in a cycle of debauchery of their own making. Drink during the day, drugs at night, oversleep the next morning and miss the only bus out of town, rinse and repeat. Even the restaurants get in on the act, with every establishment having TVs set up playing bootleg DVDs of hit American shows such as The Simpsons, Family Guy, and Friends.
With most restaurants having the same menu of bad Western food and bland Lao food, you essentially choose where to eat based on which show you're comfortable watching. Now, I'm not someone who thinks that every moment of travel must be focused on maximizing cultural experiences, but Vang Vieng really encapsulates everything about the backpacker ethos that's just totally tone deaf and clueless. You come halfway around the world to get drunk and watch Friends while going tubing every day for two weeks? And you spend all your time talking to other people who are doing the same? Couldn't you have done all of this at home?
I'll note that plenty of people make Vang Vieng a stop on their backpacking circuit and absolutely love the place. For me, I loved my time in Laos. Luang Prabang is one of the coolest towns I've ever visited. Vientiane has a really cool Graham Greene kind of vibe to it. Savannakhet has a rundown, off the beaten track charm. But Vang Vieng? Vang Vieng is there to keep the worst kind of tourism from infiltrating the rest of Laos. Proceed at your own risk.