Taking advantage of the natural lines available in architecture and urban settings can enhance the visual and emotional impact of your photos. This is because, when used well, lines can draw attention to areas of interest and create a sense of continuity that's pleasing to the eye.
Likewise, using strong vertical and diagonal lines in combination with exaggerated foregrounds will let you go beyond visual focus and artistic continuity to achieve dramatic results that draw viewers into the scene and inspire thoughts of strength and stability.
These effects are the product of human physiology, optical illusion and our conscious and unconscious associations with the surroundings and landmarks that make some of the best subjects for this kind of photography: urban parks and monuments.
Human physiology dictates that our attention is drawn to places where lines converge. Therefore, if your photo includes strong vertical/diagonal lines that converge on the strong line of the horizon where your subject is, then you've naturally increased the visual interest and impact of that subject.
Likewise, exaggerated foreground areas also provide perspective and the illusion of being in the scene and looking or even moving toward the subject. In this case "ground" is the operative word in "foreground," because by emphasizing the foreground you have enabled your viewers to picture themselves standing on that spot and seeing it in the same way.
Finally, the trick to using lines well and achieving the greatest effect is to find settings that are not too busy with lines running in many different directions, but rather have strong, uninterrupted lines capable of drawing a viewer in. Some of the best surroundings and subjects for these kinds of photos are urban parks and monuments. In general, they will already be designed for visual and emotional impact and will have clean, strong lines available without the distracting clutter of most urban landscapes and architecture.
Below are some great examples of using strong lines and exagerrated foreground to achieve dramatic results.