Billing itself as “A Compendium of the World’s Wonders, Curiosities and Esoterica,” the Atlas Obscura is an online travel guide to the globe’s most unusual, out-of-the-way places.

You’ll find out about crazy places like the Pyramid of North Dakota and the Blood Falls of Antarctica.

And if you know of a weird attraction that’s missing, there’s an upload form.

In fact, thanks to its community-building features, the Atlas is a social network as much as it is a reference site.

People who upload their own curiosities can create profiles that appear whenever you’re looking at an Atlas location. Facebook Connect allows visitors to tell their network about places like the Newnes Glow Worm Tunnel.

The Atlas has Facebook and Twitter accounts, too.

All this social networking will no doubt come in handy this March 20, when Atlas fans take to local bizzarro attractions for Obscura Day.

If we weren’t leaving our Kansas City environs for SXSW this year, we’d totally rock the Kansas Underground Salt Museum in Hutchinson, KS, or the Garden of Eden in Lucas. Maybe we’ll have to swing by the Museum of the Weird and the Bat Bridge in Austin.

Note the heroic levels of organization on the part of the Obscura Day organizers: Each destination has its own Facebook invite and Eventbrite page endowed with Google Maps and an Attendee List. Be sure to RSVP! The widget at the top of this page? Kindly provided by organizers.

These people are serious about their weirdness.

Where will you venture on Obscura Day?