I didn't really want the bridge to be anything fancy, as you don't really see a fancy bridge in locations like that. I decided to go for an unimpressive concrete bridge.
For robustness and stability I decided to go for wood and chose my long time favorite Jenga blocks. They are nicely machine cut with uniform shape and was perfect for the piers.
First I had cut the two major components of the piers from these wooden blocks - two sections, the wider base and relatively thinner piers.


Next the span of the bridge was made from a single Masonite sheet. There is a 3mm cardboard support in the under side of the Masonite board for rigidity and to gain the right height.

Then I created the side of the bridge with 10mm wide, 1mm thick cardboard:

Then the concrete lining is done using the same cardboard, but only 3mm wide:

Now putting the bridge in it's place...


Now a small video for FUN...
The bridge is now with the painting department... :)