Traveling across the Forth Road Bridge, is a sight to behold if you have never done it before and well worth it. The layout of the bridge is fantastic and well worth the view.
We went out of our way to detour to see the two Forth bridges. There are viewpoints but it is much better to actually go over them.
When one learns of the History of the building of Scotland's bridges it is nothing short of impressive and inspires respect. The Engineering is impressive most especially for the span it is making.
Impressive construction (though only for trains now) spanning the Firth of Forth, there are 2 newer bridges now for cars, buses - from the foot of one of them you can have a good overview over the old red steel bridge.
If you like bridges, it's worth trying to find a place to park and walk around. Pretty amazing structure.