Alan Sonfist caught my attention with his "Circles of Time" art, done in Tuscany. He tends to use circles to represent the continuous flow of time. On his webpage-http://www.alansonfist.com/, there is a quote stating that, "Each ring represents the narrative natural and cultural history of Tuscany." I also like the way he states that "As in war monuments that record the life and death of soldiers, the life and death of natural phenomena such as rivers, springs, and natural outcroppings need to be remembered. Public art can be a reminder that the city was once a forest or a marsh."