JimH wrote:
A water bridge for boats built over a river. Pretty amazing!

http://www.funonthenet.in/content/view/223/31/

http://www.dw-world.de/dw/article/0,,990878,00.html



BFD -- The Erie Canal had one of these in 1836 over the Genesee river

http://tinyurl.com/l55qb
http://tinyurl.com/keff4