For the first time ever, TLA will host a conference-long Geocache Challenge. Find hidden treasures as you learn about the craze that libraries and other organizations are using to attract and teach people of all ages! Geocaching is a high-tech treasure hunting game played throughout the world by adventure seekers equipped with GPS devices. The basic idea is to find hidden containers, called geocaches, and then share your experiences online. Anyone with a GPS can play. There are 1,612,911 active geocaches and over 5 million geocachers worldwide.