page_title: Log bridge
hierarchical_section_title: Log bridge
caption_attribution_description: English: Succinct wooden beam footbridge (log bridge), over swollen Alzou river (Ouysse tributary), Lot, France Français&#160;: Passerelle sommaire, formée de troncs d'arbre en guise de poutres, sur l'Alzou (afluent de l'Ouysse) en crue, Lot, France
context_page_description: A log bridge is a timber bridge that uses logs that fall naturally or are intentionally felled or placed across streams. The first man-made bridges with significant span were probably intentionally felled trees.
  The use of emplaced logs is now sometimes used in temporary bridges used for logging roads, where a forest tract is to be harvested and the road then abandoned. Such log bridges have a severely limited lifetime due to soil contact and subsequent rot and wood-eating insect infestation.
  Longer lasting log bridges may be constructed by using treated logs and/or by providing well drained footings of stone or concrete combined with regular maintenance to prevent soil infiltration. This care in construction can be seen in the French bridge illustrated below, which has well locked dry set stone abutments and a footpath leveled with boards.
context_section_description: A log bridge is a timber bridge that uses logs that fall naturally or are intentionally felled or placed across streams. The first man-made bridges with significant span were probably intentionally felled trees. 
  The use of emplaced logs is now sometimes used in temporary bridges used for logging roads, where a forest tract is to be harvested and the road then abandoned. Such log bridges have a severely limited lifetime due to soil contact and subsequent rot and wood-eating insect infestation. 
  Longer lasting log bridges may be constructed by using treated logs and/or by providing well drained footings of stone or concrete combined with regular maintenance to prevent soil infiltration. This care in construction can be seen in the French bridge illustrated below, which has well locked dry set stone abutments and a footpath leveled with boards.
caption: Simple log bridge over the Alzou in France
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