Michael's store supplies; balsa wood, paint, and jewelry pins. Simple bridge design that I saw in a 1/35 scale diorama, took some time gluing the pieces together and added jewelry pins to mimic nails. A large portion of the time was spent on the weathering. Balsa wood is a soft wood that was easy to fray at the ends and throughout the boards. Painting the bridge took two sessions approximately 6 to 7 hours at a time. The colors I used were auburn, burnt amber, gray and (surprisingly) yellow. I would suggest getting the painting done in one sitting if possible or taking detailed notes on amounts mixed. I say this because I found that there was two tones of weathering, if you can tell the left and right pillars have different shades as a result of two different sessions.
As you can see the diorama is still in progress the blue foam is insulation board from Lowe's works great to build up the hills. I place plaster to give it a uniformed rock look to it with multiple layers of different shades of brown. I also add fine sand to give it an authentic look to it, all I do to get fine sand is wait for a windy day and grab a hand full of sand and let it drop. The wind separates the heavier sand particles from the fine sand. After a few hand full's you end up with a good amount. In retrospect I suppose you can also use a small fan for this technique.