Designed as a retreat from the noise of the city, downtown Denver's newest park promises to be a favorite gathering place, with paths leading down to the edge of the South Platte River and a grove of cottonwoods surrounding a lush wetland. But the real surprise is on top of a rise at the center of Commons Park. Sunk into the earth is a stone directional marker that's intended to help you tell east from west -- but really looks like a piece of Stonehenge that's miraculously appeared along the Platte. Since the blocks of black granite are hidden from view, this is an ideal spot for getting frisky with your love or offering sacrifices to the gods.