I've done some research on common lighting setups and how they can have different affects on the final outcome. This was done to create a logical setup for my scene as well.
I have also looked at Digital Tutors' Exterior Rendering Techniques with mental ray and 3ds Max to translate the theories to actual technical practice. Even though I am using VRay to render out my animation, the main technical elements are pretty much the same in both renderers and any technique can be easily "translated" from one rendering engine to another.
I have used a 3 point lighting setup, where I have a dominant light (orangy color, high intensity) coming from behind the gate, simulating the sun. I`ve also set a fill light in front of the gate (redish color, half the intensity of the dominant light), high up in the sky and another light (redish color, but more towards the whites) in the middle of the scene to brighten things up so the details are more visible.