Touring Thailand with only the Internet as my guide.

The last time I went to Thailand, I did something daring. No, not eating ants, boxing with ladyboys, or getting cheap plastic surgery. I went without a guidebook. No Lonely Planet, no Rough guide, not even a skimpy Fodor's or Let's Go. Instead, I trusted my fate to the World Wide Web. The result was very nearly a disaster.

I went guidebook-free with some trepidation. Since my teenage years, Lonely Planet has been my traveling security blanket. Yes, the guides can be grumpy and self-righteous, and are so popular that they can turn any lost town into a grungy backpacker mecca. But Lonely Planet faithfully led me across Eastern Europe as a teenager and around East Asia thereafter, and I remain grateful. Going without felt like packing no underwear—potentially liberating but a little unnerving.

The Internet has long been terrible for travelers—full of sham sites designed to lure visitors to selected hotels, or, in Thailand's case, go-go bars. But recent years have seen the rise of a new kind of travel site, based on the user-generated content model of Wikipedia. As a confessed Wikipedia addict, sometime contributor, and true believer, I loved the idea.

The most developed Wiki-style travel site is Wikitravel. Started in 2003, it uses the same software as Wikipedia but is owned by a different company. (Two others, World Wikia and World66, are weaker.) The idea of Wikitravel is that everyone is potentially a travel writer. If you've been to the Palau Islands or Goleta, Calif., you are as likely to have a great travel tip as anyone else. Wiki software, moreover, is arguably even better suited for creating a travel guide than an encyclopedia. To explain rocket science, you need to know some. But the very first Lonely Planet, Across Asia on the Cheap, just rendered the experience of two Australian backpackers traveling slowly from London to Sydney in the 1970s. The Let's Go books are similarly idiosyncratic, written by sunnier Harvard undergrads who putter around their assigned continent. (The dirty secret is that these student-writers often use Lonely Planet as their guidebook.)

So, the innovation of Wikitravel—"built," the site says, "with the spirit of sharing knowledge that makes travel so enjoyable"—is to create a guidebook written by millions, not a select few. You'd have to be a regular sourpuss to hate the idea. But actually using Wikitravel is another story.

My plan for this trip to Thailand was based on a somewhat corny vision: I wanted to climb a limestone cliff with my bare hands and look out at the ocean below, while pursuing a mind empty of stray thoughts. That meant I had three basic questions: Where can I find rock climbing in Thailand? What kind of people go there? And where can I stay? On all three questions, Wikitravel failed to deliver—in part because it's still new but also because, ironically, Wikitravel fails to capitalize on the full potential of the Web.

I knew from a friend that Thailand has two main options for beach rock climbing. Railay Beach, in Krabi province, is the most famous climbing area in Thailand. The Phi Phi islands, the setting of Leonardo DiCaprio's The Beach, also have suitable cliffs, albeit with fewer routes. But how to choose between them?

A problem with Wikitravel is that it has a rule called "Be Fair," which is similar to Wikipedia's goal of presenting a "neutral point of view." That sounds great, but it's not really what you want in a guide. Wikitravel is too vague: Phi Phi, it said, "has a good vibe" but is "rapidly becoming less and less attractive." Railay it described as "a rock climbing hot spot, attracting climbers from all over the world." Neither of those descriptions, to my mind, did enough to exclude the possibility that my destination would also be "a favorite of naked German package tourists."

But the more serious problem was accommodation listings. This may be the Achilles' heel of Wikitravel's all-volunteer model. It's no fun visiting and ranking dozens of grimy hostels and boring hotels, especially when you're on vacation. Consequently, listings were sparse. For Railay's Tonsai beach, Wikitravel listed but two places to stay. For Koh Phi Phi, three places for the entire island. Wikitravel Bangkok, astonishingly, had no listings at all. Help!

That's when another difference between Wikitravel and Wikipedia hit home. If you're like me, you use Wikipedia to look up errant stuff you hear about randomly, like the band the Hold Steady or the last mission of the Battleship Yamato *. But you don't actually rely or depend on Wikipedia, any more than you relyon Michelle Malkin's views on Iraq. If Malkin or Wikipedia are wrong, no big deal. If Wikitravel's wrong, you're sleeping on the streets.