Subdivisions. The Ordovician is the second period of the Paleozoic era. The Ordovician began after the end of a series of extinction events known as the Ordovician-Silurian extinction events which ended around 488 mya.
As a state highpointer, Humphrey's Peak in Arizona was on my bucket list. The trailhead was easy to find. The trail itself was not well maintained and rather rocky, which wasn't too bad going up, but required a lot of caution descending to protect your knees.
Arizona Base and Elevation Maps. 1  The two maps shown here are digital base and elevation maps of Arizona. 2  This Arizona base map highlights the location of the state capitol, Phoenix, and other major cities throughout the state. 3  This elevation map of Arizona illustrates the number of feet or meters the state rises above sea level. The lowest areas of the state are along the Colorado River where a low point of 70 feet above sea level is reached. The highest point in Arizona is in the northern part of the state.