On one occasion I carried a cast fossil (mammoth jaw) about a mile over rudimentary trails, Total climb was uphill. I went slow and easy and didn't injure myself. I was going quite slow and my mobility was definitely impaired. At my request, the cast was weighed afterward - 90 pounds plus 5 pounds for the pack frame.

For most of us, not a practical prospect. A really big, fit guy might be able to carry a load that big, but it would be exceptional.