Small road bridges

[Max Rockatansky]

^^ That's interesting, a wooden deck and no roof. I thought that most wood deck bridges are covered bridges, to protect the deck from the weather.

There are still some in Florida in use that don't have covers.  It looked like the boards are mainly just sealed with something? 

[Big John]

Covered bridges were to protect the timber superstructure, which did not have treatments/sealants at that time.  Later wooden bridge decks are treated so it can withstand the elements.

[theline]

Thanks, Big John, for the enlightenment. I knew about half the story on why covered bridges are covered. Now I know the rest.