You can follow the Lewis and Clark trail a whole new way this summer, using Global Positioning Satellite technology, and G-P-S users have invented a new way to share that adventure. Hikers are sharing clues and destinations through a pursuit called “geo-caching.” and Ann Addison learned about it after she retired as teacher in Bellevue, Nebraska, schools. She started attending meetings of the Lewis and Clark commissions in both Nebraska and Iowa, and heard an idea about a “passport” system to entice people to visit both sides of the river. Addison’s husband teaches in Council Bluffs where the couple lives. She says he works with the University of Idaho on a 5-year project to explore the Lewis and Clark trail using modern technology. She decided a good project would be a Lewis and Clark geocaching trail on both the Iowa and Nebraska sides of the Missouri River, from the southern to northern borders. With a GPS unit, which is sold in sporting-goods and department stores for as little as 100-dollars, the savvy traveler can get a list of destinations left by other explorers. She calls it “kind of like a treasure hunt,” saying you go to your computer to get the coordinates of geocaching sites, the longitude and latitude that programmed into the GPS will take you right to that site. When you get to a site you’ll find some kind of container, like weatherproof ammo cans that are popular for this, and inside you can write down the date you found it and comments about what you found. Some travelers leave small souvenir items, toys or other trinkets a finder may take away — though more leave treasurers than take them. The project puts information about Lewis & Clark in the lid of the box, telling about the area where it’s found, and other travel and tourist information. In addition to the Lewis & Clark geocaching project, fans of the pastime estimate there are 600 caching sites in Iowa, and 60-thousand nationwide.