(picture taken at the stupa of BAUDHA a budhist stupa, obviously, there were many panomaric views but these prayer wheels have been my favorite since i was a kid . ok for those who don't know much about these wheels here it is -
"Tibetan prayer wheels (called Mani wheels by the Tibetans) are devices for spreading spiritual blessings and well being. Rolls of thin paper, imprinted with many, many copies of the mantra (prayer) Om Mani Padme Hum, printed in an ancient Indian script or in Tibetan script, are wound around an axle in a protective container, and spun around and around. Typically, larger decorative versions of the syllables of the mantra are also carved on the outside cover of the wheel.
According to Tibetan Buddhist belief, spinning a prayer wheel is just as effective as reciting the sacred texts aloud. This belief derives from the Buddhist belief in the power of sound and the formulas to which deities are subject. For many Buddhists, the prayer wheel also represents the Wheel of the Law (or Dharma) set in motion by the Buddha. "
so these were some info gathered from various web pages, and from personal experience all i would say is that spinning them while walking around the periphery of a stupa amidst all the mantras being chanted by the monks offering their prayers and thousands of lamps lit in the honor of deity is a divine feeling )