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.
Area code 928 in Flagstaff, Arizona, is also home to Mount Humphrey, which peaks at 12,643 feet as the highest mountain in the entire state. The Flagstaff area code split off from the 520 area code in 2001. It also covers the touristy Grand Canyon and the quaint town of Yuma, Arizona.