Hello - here is a bit of an update.

I did a bit more work on the textures and have added a barrier to stop people falling off the cliff.

I have also been working on the lights - what a headache! At the moment I am having problems with the shadows - I thought that using a directional light would give me parrallel shadows, but as you can see, I must be doing something wrong.

I also added some artificial fog - I spent the last couple of days messing around with the settings without much luck - when i zoom into my scene and render, things start to look very murky as you can see in the next picture.

Any ideas?