The true legend of trackables! 
 
The original and most popular of all trackables is still going strong! 
 
A Geocaching Travel Bug® is a unique tracking tag that you can attach to items and give them goals for others to try and complete.

Each Geocaching Travel Bug® gets its own page on geocaching.com where you can track its progress as it passes on from person to person or cache to cache.

Each Geocaching Travel Bug® comes as a pair; one bug gets attached to an item (or on its own) and sent traveling.  The other is a copy that you can hold on to or even use as a proxy.
 
Geocaching Travel Bugs® have a unique tracking number stamped into the metal tag.