My dad, I and a few other guys built 2 bridges: the 1st is a stainless steel driveway bridge, and the 2nd is a stainless steel walking bridge, both over the same ravine. Also, the driveway bridge holds 90 tons, it has 6 stainless steel I-Beams w/ 86 yards of cement as a foundation. Enjoy. BTW, these were built at our house in Elba, MN, USA. Thanks for viewing! Here's the link to the album: Driveway & Walking Bridges - a set on Flickr