Geocaching: A Global Treasure Hunt

Geocaching is a sort of global treasure hunt based on GPS technology. On May 1, 2000 the GPS system turned off its Selective Availability "feature" -- a system that intentionally introduced errors into civilian GPS access, in order to confound potential attackers. When that happened, the GPS system suddenly became reliable and accurate enough for non-military personnel to pinpoint specific locations.

A day or two later (sources disagree), Oregonian Dave Ulmer placed the first geocache (then called a "GPS stash") and posted its coordinates online:

N 45 17.460 W122 24.800

"Lots of goodies for the finders. Look for a black plastic bucket buried most of the way in the ground. Take some stuff, leave some stuff! Record it all in the log book. Have Fun!

"Stash contains: Delorme Topo USA software, videos, books, food, money, and a slingshot!"

By May 6, 2000 Ulmer's geocache had been found by two searchers, and one had logged the find in the included logbook. This event set in motion a new worldwide hobby/game in which geocaching enthusiasts hide caches (typically in waterproof plastic containers), post the location online, and wait for others to find them.

In the years since 2000, the hobby has evolved an organized online community, prompting users worldwide to strap on their backpacks and leave the house, GPS in hand. Some objects, including Geocoins and Travel Bugs, travel between caches -- seekers pick them up and move them from place to place, (usually) logging their activity in the provided logbook. Similarly, Geotokens are objects that can be traded for other items or kept for sentimental value.

Geocaching has its own set of ethics and policies, many of which are documented at Policies range from specific guidelines about retrieving and hiding items to specifics about environmental impact. Seekers should also be careful not to run afoul of Johnny Law when finding a cache -- according to Wikipedia's excellent Geocaching page:

When geocaching in busy locations, searching for a cache can require tact and craftiness to avoid the attention of the general public (also known by geocachers as "muggles"). The person hiding a geocache frequently takes this into account so that the hider and those looking for caches will not cause undue alarm. When care is not taken in hiding or finding a geocache, cachers have been approached by police and questioned when they were seen as acting suspiciously. Other times, investigation of a cache location after suspicious activity was reported has resulted in police and bomb squad discovery of the geocache. A number of caches have been destroyed by bomb squads.

If you're ready to get started, check out the Official GPS Cache Hunt Site and The Complete Idiot's Guide to Geocaching, grab a GPS, and get out there!

Readers: have you participated in the hobby? Share your geocaching stories in the comments!

China Launches Crowdfunding Campaign to Restore the Great Wall

The Great Wall of China has been standing proudly for thousands of years—but now, it needs your help. CNN reports that the wall has fallen into disrepair and the China Foundation for Cultural Heritage Conservation has launched an online crowdfunding campaign to raise money for restorations.

Stretching 13,000 miles across northern China, the Great Wall was built in stages starting from the third century BCE and reaching completion in the 16th century. To some degree, though, it’s always been under construction. For centuries, individuals and organizations have periodically repaired and rebuilt damaged sections. However, the crowdfunding campaign marks the first time the internet has gotten involved in the preservation of the ancient icon. The China Foundation for Cultural Heritage Conservation is trying to raise $1.6 million (11 million yuan) to restore the wall, and has so far raised $45,000 (or 300,000 yuan).

Fundraising coordinator Dong Yaohui tells the BBC that, although the Chinese government provides some funds for wall repairs, it’s not enough to fix all of the damage: "By pooling the contribution of every single individual, however small it is, we will be able to form a great wall to protect the Great Wall," he said.

[h/t CNN]

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YouTube // Deep Look
These Glowing Worms Mimic Shining Stars
YouTube // Deep Look
YouTube // Deep Look

The glow worms of New Zealand's Waitomo caves produce light, mimicking the starry night sky. Using sticky goop, they catch moths and other flying creatures unfortunate enough to flutter into the "starry" cavern. Beautiful and icky in equal parts, this Deep Look video takes you inside the cave, and up close with these worms. Enjoy:

There's also a nice write-up with animated GIFs if you're not in the mood for video. Want more glow worms? Check out this beautiful timelapse in a similar cave, or our list of 19 Places You Won't Believe Exist topped by—you guessed it—New Zealand's Glowworm Caves!


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