<Tr> <Th> Website </Th> <Td> www.sedonaaz.gov </Td> </Tr> <P> Sedona / sɪˈdoʊnə / is a city that straddles the county line between Coconino and Yavapai counties in the northern Verde Valley region of the U.S. state of Arizona . As of the 2010 census, its population was 10,031 . </P> <P> Sedona's main attraction is its array of red sandstone formations . The formations appear to glow in brilliant orange and red when illuminated by the rising or setting sun . The red rocks form a popular backdrop for many activities, ranging from spiritual pursuits to the hundreds of hiking and mountain biking trails . </P> <P> Sedona was named after Sedona Arabella Miller Schnebly (1877--1950), the wife of Theodore Carlton Schnebly, the city's first postmaster, who was celebrated for her hospitality and industriousness . Her mother, Amanda Miller, claimed to have made the name up because "it sounded pretty". </P>

What makes the rock's red in sedona arizona
find me the text answering this question