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  1. Standard Trail Plans and Specifications - US Forest Service

  2. Sustainable Trail Bridge Design - US Forest Service

  3. What are good designs for volunteer-buildable trail bridges?

  4. Build Your Own Trail Bridge - AQHA

  5. Sustainable Trail Bridge Design - American Trails

  6. Trail Bridges - Rails to Trails Conservancy

  7. Sustainable Trail Bridge Design - Trail Skills

  8. (PDF) Sustainable Trail Bridge Design - ResearchGate

  9. Trail Bridge Catalog - US Forest Service